When i move my left arm in certain directions at certain times i get terrible pains in the upper arm. If i start to move my arm slowly and try to stretch sometimes I can move it without so much pain. I keep stretching until I can move it without pain. At the least expected times the pains returns when i again move my arm in certgain directions. The pain starts just below the shoulder and into the bicep.
Dear sir, from your explanation you may have different things, form bursitis, arthritis, tendinitis of maybe same muscle rupture. You need to consult you doctor