Contractions? Help!! Updated,still home.

I've been having what I think are contractions since about 830ish. They haven't gotten closer together, I think. Started timing them a little while ago, and they're about 8-10 mins apart according to the app I'm using. I'm also having bad pelvic pain and I had diarrhea this afternoon. Should I call my doctor? I'm scheduled for a C-section on February 15, for when i'll be 39 weeks. Today I'm 36 weeks 6 days, and went to see my dr today had an ultrasound and baby is measuring a few days ahead, that the ultrasound technician said she didn't think I'll make it to 39 weeks but Dr didn't say anything.

Update:

It is now 12 pm, and contractions have stopped but I had them all night and morning. This is not fun!! I read online they could be prodromal contractions. I've felt Braxton Hicks before but like twice and very irregular. This was regular, and constant. I hope baby doesn't come out early, I want to wait until the 15! Lol I'm not ready !! Lol