When you are moving around, it soothes the baby so they don't usually move much until you relax, and that's usually when they go crazy. It's normal. Also, what irmadowd said was correct.
I know its totally normal to get so hot that it becomes so uncomfortable. Its because our pregnant body is making lots more blood to keep our little one growing & healthy. My bf says I'm so hot to the touch lately. Lol Don't stress, it's normal.