btw here are some things that will help. go buy a brace for your wrist. keep it on all the time and sleep with it. it should be the kind that has a metal thing in it so it keeps your wrist straight.
also buy those hot/cold packs you can microwave or freeze and wrap around your wrist. those things helped with the pain. i would have one of those heat packs and put it under the trackball for when i was working.
most importantly tho you should rest and let your body heal itself... its been like 4 yrs and i havent had a chance to let my wrst rly heal itself and it sucks :(