Stomach pain, bloating, and flatulence could be several things. Gallbladder disease, irritable bowel disease, food allergies, H. Pylori (the bacteria that causes stomach ulcers in many cases), and ulcers of the stomach - upper intestine - or duodenum.
Best thing for you to do is to let your Dr check you for H. Pylori with either a blood test or breath test. If negative, an ultrasound of the gallbladder and then possibly a CT of the Abdomen. Of course, this might be a case of ruling things out as well as looking for things, so it might take some time to figure out. For a rundown of symptoms of H. Pylori, click here.
In the meantime, you can keep a bland diet (nothing spicy or fried) and also cut down on foods that cause excess gas such as carbonated beverages and also certain foods that tend to form gas such as apples, artichokes, asparagus, beans, broccoli, brussel sprouts, cabbage, cheese, corn, fruit drinks, Ice Cream, milk and milk products (which you avoid already), onions, pasta, peaches, pears, potatoes, prunes, and whole wheat foods. Try to obtain products that have simethicone in them and take as directed. Something that is not proven but may be helpful is to take probiotic drinks such as Activia.
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