Rectal bleeding question --TMI

There is bright red blood coming from my butt. I'm 100% sure it's not from my vagina. My question is why is my butt bleeding? My stools are soft, I don't see anything on the outside, and I have no pain at all. Even with a bm it doesn't hurt. I thought it might be a hemorrhoid or fissure, but I see nothing and I thought those were both painful? It just made me panic to be 36 weeks pregnant and see blood in the toilet. I know you guys aren't doctors and I do have an appointment in the morning where I will be bringing it up. Just thought I'd ask if it's common or OK to have bleeding with no pain at all.