well like, when i use proper technique or like type, in both hands, it seems like my vein tickles when it contracts. its like an annoying tickle that i feel like i need to hit it against something for it to go away.
also the muscle in my left arm has been twitching.
i believe its the radius bone muscle. it sucks though because it hinders my guitar playing.
my right wrist is in a brace right now and i have really good technique.