Okay? I can't even walk?

Okay, I don't know where to start. I started my period, this is the third day. I had sex with my SO and my period stopped like usual (that happens everytime I have sex) but the thing is, it starts right back after I pee when we are done. It hasn't started back and it's been 2 hours. all that's coming out is alooooot of clear sticky CM like I'm fertile? we also used a condom so I know it wasn't from him. I checked the condom when we were done. I was already sore before sex and the sex hurt so bad we stopped. I mean, it's also normal for sex to be SLIGHTLY painful during my period but that hurt WAY too bad. I'm in pain, like not cramps but it feels like my uterus has been beaten to death and it's not anything like normal period cramps, I can barely even walk. It hurts to move. I had to drive home and somehow just driving hurt. If I sit down too fast it feels like someone kicked me in the vagina. This pain isn't normal, I'm all the sudden not bleeding anymore and I don't know what's happening. I also feel like I should mention that about 2 weeks ago I took the plan b.(we had a condom break because we didn't use lube)  I do not think I am pregnant because even though my apparent period was 3 days it was still heavy and had clots in it. I don't know what to think.