Well, it sounds like you are going to need to reset it.
If you haven't given it a shot yet, try to log in using your most likely password. You need to try at least once in order to trigger the reset option. Make sure at the same time that you are trying to log in through the member option and not the vendor option as this will definitely tell you that your password is incorrect.
Once your log on has failed you will notice another option to the right of the user/password fields. Click the send email button and wait a few minutes for the system to send you a link through email to reset your password. This screen will prompt you to enter your new password twice and away you go!