What is this pain??!?

So I went and got my hair done this afternoon...yay! So I was sitting for a long time. I noticed I was stiff when I stood up but it wasn't painful. I went to the grocery store afterwards and when I got out of my car, all of a sudden my abdomen tightened up like a BH but then it started to HURT! It hurt across the top of my bump like I had just done 1000 situps and got a muscle cramp. Then it kinda started to feel like I had to fart really bad. It hurt through to my back too It hurt like that most of the way through the store then gradually it went away. Once I sat back down in my car to leave it finally felt a little better but still sore.

Would a BH hurt that bad?? Could it just be because I was sitting for so long and when I stood up I cramped up?? It hurt reaalllllyyy bad!!

 

Nothing so far today. Been having some gas pains but they're completely different than what happened yesterday. I honestly thought it was a contraction. Was kind of freaking out for a second.