Yesterday I experienced the worst pain second to child birth, in my belly area.

The pain was towards the top of my abdomen, so I assume it was in my stomach. I didn't have a fever but had chills and goose bumps. I checked my temp with three different thermo's, I had them around from when my son was little. I don't understand how I can have chills without a fever but.... No vomiting or anything just bad pain. I thought gas at first, but the pain was not eleviated with burping or passing gas out the other end. No diarrhea either. The pain when it came was sharp, in my upper abdomen right below my rib cage. It cam in waves.

I have looked online and found nothing that relates to this. I almost went in to the emergency room, except I don't have insurance.

The only thing that seemed to help was a very hot water bottle. It was so hot it burned my stomach, I didn't know this until this morning, I guess I didn't feel it.
I also woke up feeling like I had just been through hell and back, I'm week and fuzzy headed today. But I feel ok, and I'm hungry, I was hungry all day yesterday during the pain, just didn't trust eating anything.
My main concern is that I was poisoned or something, and that this will come back, and that I really do need to see someone?
It also hurt more when I went to the bathroom, for some reason sitting made it hurt a lot.

I didn't eat anything I normally don't eat, I haven't been exposed to any flu, to my knowledge. I've had food poisoning before and the pain was lower in my abdomen, kinda all around with cramping and hardness. This was different. Higher and the pain was so unbearable that I was brought to my knees screaming at one point. Please help.

Thanks