When my right hand plays down below middle C and beyond, my wrist often gets tight...same when my left hand plays above middle C and beyond. It is especially tight when I have to stretch to play a chord in those positions. I don't know if you understand what I mean, but it is a noticeable problem in my technique. Any suggestions?

Has it always been a problem, or is it something that has developed over time? If it's new, or relatively new, it might be tendonitis. If it's been around for a while, it must have something to do with how you hold your hands.

Unfortunately, it's only occurred in the last year. Perhaps you're right about the tendonitis.

No reason to freak out - it could be any number of things, some of which could be resolved with something as simple as a daily dose of ibuprofen. But since it's new, I would definitely get your doctor to look at it.