I've had pain in my left shoulder for about a month now. It hurts when I move in a certain way, when I take a deeper breath, and when coughing. My doctor gave me muscle relaxers because she thinks it's a muscle strain. That has not helped. The other day I felt pain in my left arm and it went all the way down to my fingers. It hurts a lot more to make any movement when it is cold. Could this be something other than a muscle strain? My doctor has not yet seen me. She prescribed the medicine over the phone.