Over the past couple months I've been noticing that my right hand, which is my picking hand, is getting really tired and it seems like I can't even hold the pic anymore while I'm playing. The messed up part is this mainly happens during gigs! My hand seems to be fine during practice but for some reason I guess I play a little bit harder during shows. That's the last place I want to not be able to play guitar is up on stage while we still have half of the set to go.
So my question is does anybody have any warm up techniques or stretching technique that they can share with me that will get my hands able to play for long periods of time?
It sounds like you need to focus more on maintaining a light grip on the pick, or just a general look at your technique. Pain when you play harder is more of a result of doing something wrong, not that you need to get used to it and/or stretch more.