It could be appendix, constipation, gallbladder, if female it could be your overy, tubal pregnancy, etc. Depends exactly where on your right side. Your dr would be best to tell you what it is. If it is still hurting I would recomend you go back to your dr and let him know it is still hurting. They can do MRI's, ultrasounds, etc to aid in diagnosing where the pain is comming from. Go back and demand some further testing be done. Good luck!