You can reset your current password on Sign In page by clicking Forgot password? link.
Then, you will have to insert your email address in Reset Your Password form and click Send Instructions button.
You will receive password reset instructions to your email within 24 hours.
If you want to change your current password, please use the corresponding form on the Profile menu page.
To do this, insert your current password, then set a new one, and repeat the new password once again.