Shoulder

I do mostly pushups, dips, and I carry a bag for about 45 minutes a day with about 30 to 60 pounds of paper in it–the bag hangs from my shoulder.
I don’t know the mechanism of injury, but I can no longer flex my right deltoid I on top of my clavical, front to rear, from the neck to my arm. The left is fine. Pain is modest, and general soreness except for a little more sharp right at the top of the shoulder above my arm.
The muscle is completely unresponsive.
I can still curl with good weight, and I can do pushups. I haven’t tried dips, yet. Soreness increases and decreases with the amount of attention I pay to my shoulder.
Any ideas?
Jim
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