*possible*...you're pretty young but it's possible that your system just decided to wake up and say "you know what..this X food .. I don't want it anymore.." and you could be intolerant to something (anything..) much like lactose intolerant people or gluten intolerant..soy..peanuts..you name it (not allergic just intolerant) but lactose intolerance is pretty common.
so you could take out the regulars like dairy/gluten..and see if you get feeling better just as a two week trial..eat eggs for breakfast or plain white rice with salad and no toppings/dressings ...plain unseasoned meats and just give dairy a break for a week or so or do both dairy and wheat at the same time.
One thing though you said you burp and belch more after you eat with mass gas and it keeps you awake at night.. those are symptoms that *COULD* be an ulcer or an infection called h.ploryi... basically a breath test or diagnosed with a blood test. Calcium (tums) usually *helps* but I've heard it's temporary and then once the effect of the antacid wears off *it's short* then the burping and gas/pain and such come roaring back faster than ever...basically antacids do not heal ulcers caused by infection.
(I think blood test/trial is a good idea.. so going to a doctor to get that checked would be a decent idea..or a trial of acid reducers... another idea is you could go out and buy some orange juice or lemonade or eat some chips and salsa something spicy and see what happens..if it gets MUCH worse then you have some clues, but if it feels better on milk..ice cream, then it might be ulcer.. if it feels mega ton worse on dairy then it might be lactose intolerance..)
I DUNNO just some ideas - good luck :S
it gets better after i take probiotics (to regulate my digestive system) + a little yogurt. but it didnt get too bad when i ate dorritos and salsa.
weird. if it stays this bad or gets worse ill just visit the doctor i suppose. thanks for the advice.