Stomach has been constantly hard since last night 40 weeks and 3 days

I'm 40 weeks and 3 days, my stomach has been constantly hard since about 9 pm last night, its about 11 am right now. I've been having some cramps had some last night and now they came back, just about 30 minutes to an hour ago. I've also had really bad BM cramps since about 3 am this morning. Its very uncomfortable to walk, my stomach is so heavy and it just hurts to walk. It feels heavy in my lower stomach and pelvis area. In my whole pregnancy I've had this one other time and it never carried on this long. No more then an hour, but this feeling has been going on for 13 hours basically i know most of it is baby but my its hard and tight in my whole stomach.