Contractions at 30 weeks

I'm currently 30 weeks pregnant l, my fiancé and I decided to have sex last night and like 10 minutes after we were finished I started to get really painful contractions they felt like they were getting worse every single time it was a bad cramping feeling that went all the way to my lower back I was starting to feel pressure in my vaginal area like she was trying to come out my belly would get hard and tight each contraction they were two minutes apart I tried to relax switch positions but nothing seemed to help I decided to stand for a while and that calmed them down so much I finally got back into bed and could only fall asleep at the end of my bed I was debating on going to the hospital but it's way to soon for her to come out right? Did this all start because of sex?