diff --git a/src/lib/types/account.ts b/src/lib/types/account.ts
index fffbbf6..027131f 100644
--- a/src/lib/types/account.ts
+++ b/src/lib/types/account.ts
@@ -6,10 +6,10 @@ export const changePasswordSchema = z
     newPassword: z
       .string()
       .min(8, 'New password must be at least 8 characters.')
-      .regex(/(?=.*[A-Z])/gm, 'New password must contain at uppercase letter.')
-      .regex(/(?=.*[a-z])/gm, 'New password must contain at lowercase letter.')
+      .regex(/(?=.*[A-Z])/gm, 'New password must contain an uppercase letter.')
+      .regex(/(?=.*[a-z])/gm, 'New password must contain a lowercase letter.')
       .regex(/(?=.*\d)/gm, 'New password must contain at least one number.')
-      .regex(/(?=.*\W)/gm, 'New password must contain at least one special character'),
+      .regex(/(?=.*\W)/gm, 'New password must contain at least one special character.'),
   })
   .refine((schema) => schema.newPassword !== 'Password123!', {
     message: "You can't use the example password, silly",
@@ -25,8 +25,8 @@ export const changeUsernameSchema = z.object({
     .string()
     .min(3, 'Username must be at least 3 characters.')
     .max(15, 'Username must be no more than 15 characters.')
-    .regex(/^(?![A-Z])/gm, 'Username cannot contain uppercase letters')
-    .regex(/^(?=[a-z0-9-_]+$)/gm, 'Username cannot contain special characters'),
+    .regex(/^(?![A-Z])/gm, 'Username cannot contain uppercase letters.')
+    .regex(/^(?=[a-z0-9-_]+$)/gm, 'Username cannot contain special characters.'),
 });
 
 export type ChangePasswordSchema = typeof changePasswordSchema;
diff --git a/src/lib/types/signup.ts b/src/lib/types/signup.ts
index f343afc..7f198e0 100644
--- a/src/lib/types/signup.ts
+++ b/src/lib/types/signup.ts
@@ -7,15 +7,15 @@ export const signupSchema = z
       .string()
       .min(3, 'Username must be at least 3 characters.')
       .max(15, 'Username must be no more than 15 characters.')
-      .regex(/^(?![A-Z])/gm, 'Username cannot contain uppercase letters')
-      .regex(/^(?=[a-z0-9-_]+$)/gm, 'Username cannot contain special characters'),
+      .regex(/^(?![A-Z])/gm, 'Username cannot contain uppercase letters.')
+      .regex(/^(?=[a-z0-9-_]+$)/gm, 'Username cannot contain special characters.'),
     password: z
       .string()
       .min(8, 'Password must be at least 8 characters.')
-      .regex(/(?=.*[A-Z])/gm, 'Password must contain at uppercase letter.')
-      .regex(/(?=.*[a-z])/gm, 'Password must contain at lowercase letter.')
+      .regex(/(?=.*[A-Z])/gm, 'Password must contain an uppercase letter.')
+      .regex(/(?=.*[a-z])/gm, 'Password must contain a lowercase letter.')
       .regex(/(?=.*\d)/gm, 'Password must contain at least one number.')
-      .regex(/(?=.*\W)/gm, 'Password must contain at least one special character'),
+      .regex(/(?=.*\W)/gm, 'Password must contain at least one special character.'),
     verify: z.string().nonempty('Passwords do not match.'),
   })
   .refine((schema) => schema.password !== 'Password123!', {
diff --git a/tests/updatePassword.spec.ts b/tests/updatePassword.spec.ts
index cd08312..ee6f5b2 100644
--- a/tests/updatePassword.spec.ts
+++ b/tests/updatePassword.spec.ts
@@ -46,16 +46,6 @@ test.describe('Password Update Form', () => {
     await expectError('Invalid password', page);
   });
 
-  // Test validation error for weak new password
-  test('should show validation error for weak new password', async () => {
-    await currentPasswordInput.fill(currentPassword);
-    await newPasswordInput.fill('weak');
-    await submitButton.click();
-
-    // Check for error message
-    await expectError('New password must be at least 8 characters.', page);
-  });
-
   // Test empty fields validation
   test('should show validation errors when fields are empty', async () => {
     // Leave fields empty and try to submit
@@ -65,6 +55,56 @@ test.describe('Password Update Form', () => {
     await expectError('Password must not be empty.', page);
   });
 
+  // Test validation error for missing uppercase letter
+  test('should show validation error for password without uppercase letter', async () => {
+    await currentPasswordInput.fill(currentPassword);
+    await newPasswordInput.fill('password123!');
+    await submitButton.click();
+
+    // Check for error message
+    await expectError('New password must contain an uppercase letter.', page);
+  });
+
+  // Test validation error for missing lowercase letter
+  test('should show validation error for password without lowercase letter', async () => {
+    await currentPasswordInput.fill(currentPassword);
+    await newPasswordInput.fill('PASSWORD123!');
+    await submitButton.click();
+
+    // Check for error message
+    await expectError('New password must contain a lowercase letter.', page);
+  });
+
+  // Test validation error for missing number
+  test('should show validation error for password without number', async () => {
+    await currentPasswordInput.fill(currentPassword);
+    await newPasswordInput.fill('Password!!!');
+    await submitButton.click();
+
+    // Check for error message
+    await expectError('New password must contain at least one number.', page);
+  });
+
+  // Test validation error for missing special character
+  test('should show validation error for password without special character', async () => {
+    await currentPasswordInput.fill(currentPassword);
+    await newPasswordInput.fill('Password123');
+    await submitButton.click();
+
+    // Check for error message
+    await expectError('New password must contain at least one special character.', page);
+  });
+
+  // Test validation error for using example password
+  test('should show validation error for using example password', async () => {
+    await currentPasswordInput.fill(currentPassword);
+    await newPasswordInput.fill('Password123!');
+    await submitButton.click();
+
+    // Check for error message
+    await expectError("You can't use the example password, silly", page);
+  });
+
   // Test update functionality
   test('should successfully update user password', async () => {
     await currentPasswordInput.fill(currentPassword);
diff --git a/tests/updateUsername.spec.ts b/tests/updateUsername.spec.ts
index e3c0128..8e0d1ab 100644
--- a/tests/updateUsername.spec.ts
+++ b/tests/updateUsername.spec.ts
@@ -32,7 +32,7 @@ test.describe('Username Update Form', () => {
     await submitButton.click();
 
     // Check for success message
-    const successMessageLocator = page.locator('p.text-sm.text-green-500:has-text("Username updated.")');
+    const successMessageLocator = page.getByText('Username updated.');
     await expect(successMessageLocator).toBeVisible();
 
     // Verify the username displayed in the UI has been updated
@@ -40,19 +40,6 @@ test.describe('Username Update Form', () => {
     expect(updatedUsername).toBe(newUsername);
   });
 
-  // Test invalidator
-  test('should show validation error for invalid username', async () => {
-    await usernameInput.fill('a');
-    await submitButton.click();
-
-    // Check for error message
-    await expectError('Username must be at least 3 characters.', page);
-
-    // Ensure the username wasn't updated
-    const currentUsername: string = (await currentUsernameElement.textContent()) || '';
-    expect(currentUsername).not.toBe('a');
-  });
-
   // Test that new and old username can't be the same
   test('should not allow same username', async () => {
     const currentUsername = await currentUsernameElement.textContent();
@@ -72,4 +59,49 @@ test.describe('Username Update Form', () => {
 
     await expectError('Username taken.', page);
   });
+
+  // Test validation error for username less than 3 characters
+  test('should show validation error for username less than 3 characters', async () => {
+    await usernameInput.fill('ab');
+    await submitButton.click();
+
+    // Check for error message
+    await expectError('Username must be at least 3 characters.', page);
+  });
+
+  // Test validation error for username more than 15 characters
+  test('should show validation error for username more than 15 characters', async () => {
+    await usernameInput.fill('abcdefghijklmnopq');
+    await submitButton.click();
+
+    // Check for error message
+    await expectError('Username must be no more than 15 characters.', page);
+  });
+
+  // Test validation error for username with uppercase letters
+  test('should show validation error for username with uppercase letters', async () => {
+    await usernameInput.fill('Username');
+    await submitButton.click();
+
+    // Check for error message
+    await expectError('Username cannot contain uppercase letters.', page);
+  });
+
+  // Test validation error for username with special characters
+  test('should show validation error for username with special characters', async () => {
+    await usernameInput.fill('user@name');
+    await submitButton.click();
+
+    // Check for error message
+    await expectError('Username cannot contain special characters.', page);
+  });
+
+  // Test validation error for empty username
+  test('should show validation error for empty username', async () => {
+    await usernameInput.fill('');
+    await submitButton.click();
+
+    // Check for error message - assuming there's a custom message or using the min length one
+    await expectError('Username must be at least 3 characters.', page);
+  });
 });