Optometry just diagnosed me with giant papillary conjunctivitis but I have never worn contacts. He prescribed prednisalone. Says something could have?

Could be GPC. Most giant papillary conjunctivitis in this country is related to contact lens solution allergy but some can occur without this stimulus. Prednisone eyedrops are the standard treatment but might have some side effects. Suggest that you see a real doctor, an ophthalmologist , for a second opinion.