Unfortunately there's not much you can do but bear through the pain.  If it's that uncomforatable I would suggest asking your surgeon what he receommends. 

I am on pain meds that I take prior to bed, so they help a lot.  It's just the initial positioning trying to get comfortable that is the hardest part.  Once I fall asleep, I'm out for hours and have no real problems.  Sometimes I find myself sleeping on my back instead of side/stomach all because of painful spots - which of course being mid-radiation doesn't help matters either.

Maybe you could try to take some tylenol pm or advil pm and see if that helps releave the pain long enough for you to fall asleep comfortably?

Good luck - hopefully once the implants are in you will feel more comfortable!

Angi