problem with my right hand ( fretting hand, I'm lefty )

[Creeping Death]

Okay, I've been playing guitar for a while, I've never had bone problems. Now, I'm getting length problems. If I play something with lots of stretching, or something rather quick, but on the lower frets, I get cramping in my right hand, which IS FUCKED up. I've never, EVER, gotten this problem. Even on my first months of playing, when I was younger. Now I get problems? Can't be anything serious, maybe just overuse? Anyone have a solution, like a rubbing thing, or a pill, something....

 

[-Gavin-]

ALWYS ALWAYS ALWAYS warm up your hand before playing!!!!
THis happened to one of the importal guiatrists, played too fast/stretched too much with out warming up and now he can barely play anymore.

Think, if you go out for a spring with out warming up, 2seconds later you're lying in a mangled heap on the floor, guitar is no different, warm up before hand.