Are you sleeping on your sides? Or flat on your back. I have a pinched never in my lower back and have extremely painful and strong muscle spasms I have found that sleeping on my sides and putting a pillow in between my legs when I sleep helps a lot. When I was pregnant I lost all feeling in my legs and hips and doctors told me that is because the baby was laying right on a nerve. I would think that also sleeping wrong could do the same put pressure on a nerve.