There was a recent article that I read which debunked the existence of carpal tunnel syndrome altogether, lumping it with other "hysterical" conditions that swept through society and then disappeared. That being said, repetitive motion injuries do exist, but in all likelihood you have tendonitis.
The best therapy for that condition is to STOP DOING what caused it, i.e., five hours of computer activity per day. Go outside and take a walk, go to the gym, read a book, etc. Resist any temptation to go back to the activity for a couple weeks and then try it again but gradually work your time up. If you feel any pain, stop immediately. The problem with tendonitis is that it can take weeks to heal completely, and you can set that time back if you try to return too quickly.