IBS with pregnancy

I'll be 22 weeks tomorrow, I've had ibs since I was 9 or 10, ever since I turned 16 weeks, pooping has been a royal bitch. With the pains and aches, and not being able to tell round ligament pain from a shittin pain. It makes be wonder if i be able to tell the difference between a shittin pain or contractions.

What can I do? Or how do I cope?