A lot of folks here are giving you cautious well meant advice, and all I want to do is add to that -even though it counters what's been said. Bear in mind that everyone is different, and everyone's body reacts differently.
A number of years ago, I was playing guitar an awful lot. I had it in my mind that since guitar playing was my job, I'd put in 8 hrs. of guitar playing each day, mon. to fri. After a couple of weeks or so, I started to notice that my fretting fingers were swelling up like sausages, and becoming tender and sore. Stubbornly, I figured that I'd just play thru the pain. Surprisingly, after a couple of weeks, the swelling decreased, and the pain subsided, and I continued to play on thru. I WILL admit that it was hell for a while, and that I had to make sure that I didn't keep doing the same things over and over for too long. I also found that Krazygluing my fingernails down to my fingertips helped. (I was doing a lot of bending)
I guess what I'm trying to say here, is that some pain is to be expected -especially if you're playing a lot, but try to be 'smart' about things. Try different exercises if you find yourself 'seizing up' after a while, and take the time to think about what you are doing.
Oh yeah: I also found that soaking my hands in very hot water, and then switching to very cold water helped. I'm no doctor, but it worked for me.
Good Luck!