This shoulder thing can be really nasty. Regardless how much experience you have, sometimes your mind will not back down...
However,
1. try shoulder dislocations with a broomstick. Take a wide grip, like you would do on the shoulder press. don´t try to go narrow!
2. take a tennis ball and put it in a sock, then lean against a wall while you hold the upper end of the sock and start massaging the shoulderblade of the hurting shoulder by rolling arround. This works also when you lie on the floor (I know it´s a different area, but try it though).
3. roll your shoulders often, try to get a feeling for the shoulderblade of the hurting shoulder and push it in. I know this sounds strange, but it helped when everything else failed and my workouts became a torture!
4. see a doctor that is a sports-physician, not an ordinary orthopedist, because (some of them) they just don´t understand our diseases and what
we do.
One year ago I had shoulderpain after some sick workouts. I got told too that it was a rotator cuff injury. But when my doctor checked the shoulder on screen, he couldn´t see anything. He said that it´s just overstrained, and that the condition will take some time to wear off.
One year later my shoulder still nags now and then, but my strength increases while the pain gets less.
I hope you can use some of this information, and I wish you a speedy recovery.