Hi 103JLT,
I'm sorry to hear about the wrist pain you're experiencing as a result of your Apple Watch.
Something that could help with this would be a new Apple Watch band. If you're using a more stiff, silicone band such as the Sport Band, or a heavier band such as the Milanese loop, you can try purchasing a new band such as the Sport Loop, which features a soft and breathable woven material. If you think the problem you're experiencing is because your Apple Watch is too heavy, and is weighing down your wrist, you may want to try purchasing a smaller Apple Watch or one of the lighter aluminum models, and selling your other watch.
Hope this helps!
-Dallen