I am a tummy sleeper normally & I have fond my body pillow to be a total godsend!
I still wake every hour and a half to pee, but if I don't turn on any lights on my short trip to the loo, I can stay half alseep.
The only downside to the body pillow is the room it takes up in the bed and the jealousy is causes DH!
It gets more cuddles than he does!

Being tired I think is just part of the "joys" isn't it?
I wonder even if we got enough sleep whether we'd feel all energised??
Sleep when you can, if you need a nap take it!