So I've had this horrible pain in my left arm for three days, starting from my shoulder blade/neck right down to my finger tips. It came on over night and I've three possible suspects.

1. carrying a heavy bag on my left shoulder for a few hours on saturday
2. reading a massively heavy book in bed and holding up the heavy side with my left hand

or...

3. carpal tunnel...

The last one I've read about and I can't remember ever having any other symptoms. The confysing thing is, it's not my right arm.. my right arm which I also draw with for hours with, which regularly aches after such sessions.. Not that I'm complaining about it being my left, just a bit bewildered.
I'd like the owie to go away now plzkthx, I can't sleep properly with it and wake up in pain which is never a nice thing.