39 weeks

Been havimg really bad back paims since 5pm. Tried sleepimg to see if that helps but its not. For the past maybe hour its been on my left side, and it sometimes radiots to my left side of stomach and that side gets kinda hard and then goes to my right side of stomach and kinda gets hard. The back paims radiots every like 10-15 to every 10-20 mins and hardening happens when it does. What is this?