Help... Lots of pain... 35w5d

Kori
So I am 35w5d and I am having massive pain that wraps from my back to the front lower abdomen... And I had upper abdomen pain which has been coming in bouts... I have been trying to lay on my side to get it to subside and it has not... And I wasn't active when this all started over an hour or so ago... The pain has been relatively steady for the last two hours...
Earlier today I was out shopping and had to stop to breathe from contractions, but these don't feel the same... 
I have two other kids born at 36w4d and 36w2d... And with the second I had really bad back labor and this doesn't feel like that... 
What would you do??