Hi. didn't eat much earlier , only fajita salad , then later applesauce & pineapples then had lemon & acv water. upper prt of stomach burns ..ideas?

It sounds like: you put a number of things in your stomach that could have the potential to be irritating, possibly more so in combination!Often fajitas are spicy with onions and peppers, let alone the meat. Pineapple, lemon .. your stomach likely has secreted more acid resulting in the burning sensation you feel. Eat blander food for a day or two, consider an OTC antacid.It should resolve quickly.If not, see doc