If you are having troubles logging in it is likely related to the password you are using. First check that your password is correct by copy and pasting it from where you received it from. The password is case sensitive, and will not work if there are any trailing spaces.
If you've registered with Eventbrite, your password is your Order # and is posted in the confirmation email that Eventbrite sent you when you registered. It's a 9-digit numeric number like: 493118020