Me: T8 burst fracture, complete, spinal fusion from T10-T5, 4.5 months since accident.

Recently (within the last two weeks) something weird has started happening. After I have been sleeping for a while and I wake up my legs are covered in sweat. So much so that the first time it started happening I thought I had had a bladder accident. I never feel hot, in fact the opposite. I usually have to sleep with a pretty heavy comforter or I get the chills. Last night I tried sleeping with just the blanket over my chest and left my legs exposed. I woke up and my legs were cold and still covered in sweat. Aside from the nuisance of having to change my sheets every night it is a bit worrisome. Is this common and is there a cause and possibly a solution?