Yes, definitely check in with your doctor as it could be something compression related or like you said, a nerve that is acting up when you are laying down in a certain position.
I used to get numbness in my arm (the side that I predominently slept on) until I finally broke down and got an ergonomic pillow. It was hard to give up my favorite soft/squishy pillow for something that felt so structured and not cuddly...but I have to admit, it helped and the problem is gone!
Good luck getting the answers you need regarding this.
S.C.