Hand specialist. Get checked out for carpal tunnel syndrome.
Keyboard. Besides trying out different keyboard set ups and arrangements, stetching, nsaids and making sure there is no underlying issue such as trigger finger, carpal tunnel, arthritis and other common hand and wrist isssues is essential http://www. Handctr. Com/common-finger-hand-wrist-forearm-and-elbow-problems. Html.
Take breaks, and... If keyboard is lower than desk surface, tilt the back edge of the keyboard slightly down. Keep wrists in a neutral (straight) position—not bent up or down. Keep elbows at a slightly open angle-90˚ or greater. Keep shoulders relaxed, and elbows at side. Don't use wrist rests or armrests while typing-only while resting. If you have a broad chest, consider a "split" keyboard.