Leg cramps

Anyone else getting bad cramps in their legs? I'm 11 weeks and I'll get a cramp in my left leg (calf) in the middle of the night, it hurts so bad. I've noticed that when I sleep on my back I cross my ankles for some reason I think that might be why it's happening but I can't really not do it because it happens when I'm asleep. Any advice to keep this from happening?