I’m currently 36 weeks and it’s been uncomfortable for me to lay on my left side ( which is recommended) my entire pregnancy. Finally on Friday I woke up with pain in my back. Went to the hospital on Sunday and they said it’s a muscle strain on my left side. I see a chiropractor already, but I don’t know how it happened. The baby mostly lays on my left side, so this could have something to do with it. Since the strain I can only lay on my right side. What could have caused this if I haven’t done anything differently?