My period

So it’s that time of the month and I believe I’m about my fourth or fifth day in. Well earlier in one of my classes my (what I believe to be my uterus) just start giving me horrible cramps. I had to leave because I thought I was going to have to get in the fetal position. The whole ride home I’m trying so hard not to cry because I’m freaking out and almost falling asleep. When I get home. I am freezing. It is new weather and it’s about 63 degrees outside. But I HAD to bundle up in my heaviest clothes and I took a nap. Now normally I’m one who is never cold I’m always hot so this was a shocker to me. It’s been about 3 hours and now I’m kinda hot. So I strip down and just stay omg the bed but I know I’m probably about to start freezing again. So there are cold and hot flashes, then my whole body aches, but I had four performances yesterday with my show choir so I want to believe that’s why I’m so sore. Lastly I am extremely fatigued. I didn’t get any sleep last night ( the reason for the nap) and I should be feeling better but honestly I could pass out again. Can anyone tell me what is going on???