I've heard of a couple things that may help strengthen your wrists.
If you have hand weights or a body bar (light bar maybe 6-10 pounds). You dont' want to do this with heavy weights. Start light if its individual hand weights 3-4 lbs.
One if your sitting in a chair, with your feet firmly on the ground. Put the back of your forearms on top of your quads (top of legs), hands facing up with the bar or weights in your hand. Then just using your wrists, do some little curls. Just with the wrists, you don't use the rest of your arm. Think bicep curls for the wrists?
The other one is like a motor cycle looking motion. Think old style with the big harley type handle bars.
If your doing a bicep curl and your at the top of the motion. Except your hands are facing down away from your body. Then slowly do the opposite motion of the other exercise. You start with your wrists straight, then slowly tilt them down, and back up.
If your in lots of pain, maybe try some advil, but maybe take a break and ice the area to help with any inflamation. Ice is way better especially if you have any stomach issues as the advil (or other nsaid) will upset.
Some other things. Play the piano in the air to relax your fingers, and wrists. Close and open your hands. Plus, don't forget to take breaks every so often. You will probably need to take more breaks since your having lots of problems.
If you got some $$$$. A good massage therapist can help those tired hands, wrists, forearms. But you have to find someone good, who can look for any trigger points or knots in your hands, forearms.
Also if you have any neck pain, shoulder pain issues, they sometimes can reflect pain down into the hands. Again a good massage therapist will ask you if any of your fingers hurt and which ones.
Good Luck,
Connie