Ugh. Don't get me started. I've got that and more. It will get better if you stop using it (your wrist). However, because it's your wrist it may also be Carpal Tunnel which is totally not cool and usually requires surgery. Tendonitis is an inflamation of your tendons usually caused by overuse. Take it easy and try not to use your wrist for a while and it should feel better. There is not guarantee that it will go away.
Also- Not to nitpick, but it's t-e-n-d-o-n-i-t-i-s and Spubba, it's b-u-r-s-i-t-i-s. They aren't really the same thing, either. At the core, they are because they're both inflamations, but tendonitis is an inflamation (swelling) of your tendons while bursitis is an inflamation of your bursa which is the sack that keeps your bones from rubbing together at your joints.
I only know because I have them both. Bursitis in both shoulders (near my rotator cuff) and sub-scapular tendonitis. And plantar faciitis in my feat. My doctor also thinks I might have carpal tunnel in my hands and part of my wrists and arthritis in my knees and neck. I'm on perscription medication for all of them.