All day today I have been having this tight squeezing feeling in my upper Left arm just below my shoulder. For the last 10+yrs when ever I rotate my arm my shoulder pops and clicks. But today I feel as if something is just squeezing my arm and pinching it. Kinda like a blood pressure cuff when it get s real tight on your arm. I have almost no strentgh in my arm. When I squeeze my hand it's very weak. Just wondering if anyone has any ideas as to what this may be.