Pancreatitis, gallstones and gastritis cause upper stomach pain and bloating, according to WebMD and the University of Maryland Medical Center. In pancreatitis, the pain is often felt in the upper left quadrant of the abdomen and is worse after eating, especially if the meal is high in fats.
The pain for pancreatitis is also severe and long-lasting when the patient lies flat on his back, explains the University of Maryland Medical Center. It may also radiate to the left shoulder or to the back. Along with these symptoms are fever, nausea and vomiting. The patient may also pass clay-colored stools, feel gassy and uncomfortably full, and suffer from indigestion and hiccups.
The symptoms of gastritis are similar to the symptoms of pancreatitis, states WebMD, though the patient also suffers from a loss of appetite. He may also vomit blood or material that looks like coffee grounds, which is a sign of bleeding in the stomach. His stools may be black or tarry, which also signals bleeding in the stomach. The symptoms for gallstones are much like the symptoms for the other two conditions, though there is no bleeding into the stomach. Gallstones may cause symptoms when blocking the bile ducts.