You need to contact the credit reporting agencies: Equifax, Experion, and Transunion. They each have a website, just put ".com" after the name. These three credit agencies are obligated by law to provide one free credit report (each) per year. Pull your credit report and if there's anything on there that you personally did not authorize, then contact that credit agency and tell them to "flag it". Then contact the bank that any potential loan was drawn from (the bank info will be on the credit report) and tell them it's a fraud and to put a hold on that loan.
You can contact FAFSA and inquire if your Social Security number has been used by anyone. You need to give them your Social Security number and they will check it for you.To get their contact information, go to https://fafsa.ed.gov/contact.htm.