I realize it's a late reply, sorry. But no, no one can see your Credit Card info, not even you. When you (or anyone else) signs in, all you see is the last 4, or the first 4, can't remember, digits of your card. In order for someone else to log in they would need your password, but iTunes still conceals the credit card info. Best thing for you to do, assuming you remember the exact e-mail & password you used to create the iTunes account, is to log in, go to account information, you'll see the incorrect e-mail address next to 'Apple ID', simply click edit, change the e-mail to your correct one, and confirm when it asks you. Make sure it's your correct e-mail and choose a secure password, but one you can easily remember.