Hey Orange, you really should see a doctor. The area U describe sounds close to the kidney area and that's nothing to mess around with. It could be a lot of things. I know I said earlier to go to an Orthapedist, but you should just go see an Internist and have a check-up. Easy for me to say, I didn't get regular check-ups when I had insurance from my employer, and now they are going to take it away and I won't be able to afford it. Go figure!
Sorry I'm rambling... let us know what happens.