What is going on with my mouth?

For about 2 years, when I eat something my tongue and inner cheeks in my mouth get swollen. and stays like that for at least a week. I got these rreactions from hamburgers (pattie,ketchup,buns), cheereos, and today i gotten REALLY swollen from 1 atomic bomb (candy). Whats going on? I tried sucking on ice, taking 2 antihistamines every 3-4 hours, i tried eating sumthing i can tolerate, but nothing does the fix. What should I do?