Food intolerance/allergy to Bananas and Pineapples?

[SaraMae]

Until I was about 7 (I am 21 now) I used to eat alot of bananas and never had a bad reaction. I never really ate pineapples. Now, I can't eat bananas without a reaction that lasts for 3 to 4 hours, and pineapples don't have as bad of an effect, but it still is far from pleasant. Nothing seems to be respitory and my skin doesn't itch. It's all in my stomach and intestines, but the pain can get very, very intense, sometimes draining me of energy for days. It starts as burning in my stomach and works it's way outward until it feels like my skeleton is going to shatter if my muscles pull any tighter. It took me a long time to figure out what was causing this. I would appreciate if anyone could tell me anything or give me any helpful links. It's possible there are more things I shouldn't be eating that I don't know about yet! (Also, interestingly, I can eat banana bread with no adverse reactions...)