As others have said, pain in your fingers is part of learning to play guitar.  You're pressing down on little bits of steel wire, and your fingers don't like it at first. If the pain is in your finger tips, that's normal, and you're just gonna have to play through it.  If other parts of your hand start hurting, that's when you need to stop. 

Try and find a teacher who can look and make sure you don't have any technique problems.  That can not only slow your progress, but can lead to things like making your carpal tunnel worse.  Also, a teacher should be able to tell if your guitar needs a setup adjustment.  Really high action just adds to your workload.

I'm gonna have to disagree slightly with bagginsbill when he says that anybody can become great with 10,000 hours of practice.  First, I think it's a bit of an oversimplification.  Simply putting in the time isn't enough.  What makes you better is practice, properly focused.  If you're trying to play something, and getting it wrong, stop, back up, and if necessary, slow down until you can play it properly at the slower tempo.  Then, work your speed back up.  That way, you're not practicing mistakes.

Also, some people just have more talent in some areas than others.  Give me 10,000 hours, and I could probably do a decent job hitting major league pitching.  Give me  1,000,000 hours, and I probably wouldn't be able to hit like Ted Williams in his prime, because I wasn't born with some of the physical gifts he was.