Click on 'Profile' button on the 'Log in' dialog to bring up the profile window, you must provide the username & password if you are not already logged in.

Here you will not only see your user profile but also can update your profile except your username. Click the 'Update' button while you want to finish updating your profile.

If you are a prepaid account holder, you will see your account credit balance in the lower left on the profile window.

Viewing profile when you are not logged in doesn't deduct credit from your account nor logs you in.