Constant cramp?

Hi all, I’m 34 weeks, I went to the mall today and walked around for a few hours spending gift cards, I started getting a really bad cramp in my lower belly and hips and we decided to leave. Well it’s been about 3 hours now and I’m still having pain. It’s not a come and go type pain like a contraction, it’s constant pretty much. It eases a little when I sit down but once I’m up it gets intense again. Except now it’s in my lower belly, hips and lower back too. Like a dull ache that intensifies. I don’t think it’s contractions bc the pain doesn’t really stop just let’s up some. What could be going on?