The pain is like frequent spasms that come and go every 30 seconds approx. I have had it for two days now, the pain intially woke me up in the middle of the night. It is located in the centre of my ribs,at the top and when it spasms it is like it is gone straight through to my back. It is like it is located at the top of my stomach or in the duodenum.

What could this pain be? It's very uncomfortable and I am also very bloated and have headaches, I don't know if that has anything to do with it though. Could it be a sprained muscle from a gym workout?

I should probably also mention that I am bulimic and have been on and off for ten years, the last time I purged was Saturday.