I've been doing boxing for a little over a year and I recently started muay thai, I'm about 2 months in. Lately I've been having problems with my left thumb.. It seems after a while of hitting focus pads I get some pain in it and it gets hard to hit with my left hand without feeling the pain in my thumb. At first I thought it might have just been a couple of hooks that I threw wrong and stubbed my thumb a bit, but I find every day even after throwing a few jabs now it starts to hurt.. I'm really not sure what the problem could be, my instructor says my technique has been fine, and I even wrap my wrist/thumb a few extra times to prevent this problem but it doesn't seem to help. Anybody have a similar problem or suggestions/opinions to what could be causing this?