Couldn't sleep last night with a stomach ache which I attributed to one too many chocolate chip cookies, but upon waking this morning, I feel a very intense and burning tightness up the right middle of my abdominal area in a line to my ribs. It feels a bit like a pulled muscle, but since I've never really had much in the way or core muscles, it is a very foreign feeling. I have been doing more ab work lately but last night was not an ST night. Could this be just a delayed reaction to an over-worked muscle or group of muscles? Of course I have to move my office today and then work at the gym later, so there's no resting it today. Help?