i think you should be checking if you used the right paypal email when you signed up, also you could just visit your aff link and click on buy, and when it takes you to paypal, you can check to which account it redirects... try to login with the same account with which you have signed up, and if paypal shows an error that you can't pay to your own account or something, then its your account thats registered for sure. If it logs in, well, you made a bloody mistake and have been making money for someone else