How can I cure a stomach ache?

So ive been having stomach aches like all the time then the doctor told me I had celiac disease(wheat allergy) but I still get stomach aches and last time I had a stomach ache when I ate cereal which contain wheat and I was dumb enough not to check and now my stomach hurts everytime I eat is it because I ate the cereal or is it that I dont have celiac disease and its something else going on with my stomach