tmi topic!

Okay so I'm 20 weeks 5 days and I just went to use the rest room and while I was trying to and pushing I had this terrible pain in my lower abdomen it was like a cramping feeling I'm still getting it right now it hurts so bad and it feels like it's where my uterus is or around it I'm very concerned about this before hand I was fine but as soon as I tried to use the restroom I got severe pain is this normal? Or something I should be worried about I'm a first time mom so I'm a bit clueless too things