I am having extreme legs cramps and sharp hip pains as well when I am sleeping, it wakes me up. I tried sleeping with a pillow between my legs and that seems to help a little bit. Also when I wakes me up I go and take some tylenol.. it doesnt do much but it helps a little.
I have been having similar pains but is more in my legs/hips. Everytime I sleep during the night this sharp pain wakes me up on my right hip/leg sort of like cramping pain. It's kind disturbing...I didn't even go to work today b/c i barely got any sleep last night from it. I can tell my belly has dropped big time....more frequent trips to the bathroom for sure.
It sounds like that could be it. I hope you feel better soon. I am having a lot of problems and just put a call into the doc this morning to see if my doc will just induce and to see when. I am just in so much pain, I can barely function and I have lots of other kids to take care of. This is making it very difficult to do that and today is the first day of school too!!!
Anyway, I hope you feel better soon :)