I am a relatively new knitter and at first my hands were KILLING me! Partly because I was tensing up and anxious about what I was trying, and also because I get obsessive and wouldn't stop to take a break. I use a computer at work, too so there's your double whammy.
I started some stretches, made myself take breaks more often, and once I got more comfortable with what I was doing, it seemed to ease up. Also, I got some good quality needles so the yarn slid over them, and I wasn't having to force anything.
I was lamenting about this to a friend who also knits, and she said, "Awwhh, just suck it up; your hands will get used to it," which also sort of turned out to be true. All of the above seemed to coalesce into being able to do it without too much pain (over a month or so). However, if the pain HADN'T gone away, I would've taken a break and just READ obsessively about knitting. I also ordered a video about stretches for carpal tunnel syndrome, but I never had to use it! HTH