I have a small bulge on my upper right side under a rib cage. it comes and goes and it is painful to touch. usually it happens after exercise.

Get examined: The best advice I can offer is to get a history and physical examination by a good doctor. It may be a hernia, the chance of this would increase if you've had an operation in the area. it may even be a normal variation of standard anatomy. The best way to evaluate it is with a physical examination. Ask the doctor to examine you while you simulate the circumstances of its occurrence.