Definitely start with ice and rest for the time being, and go see an ortho. You've got to let the initial inflammation subside, and you need to know if you've torn anything. If you're just looking at inflammation (no tears or actual structural damage), continue reguar ice and heat treatments, start working on some basic rotator rehab exercises, and find an Active Release Techniques (ART) practitioner. It's a highly successful form of therapy for injuries like this, and is designed to treat the underlying imbalances in the body. It's not voo-doo, I promise. I used it with tremendous success to avoid shoulder surgery TWICE, and I know a lot of others have had great success with it, too.
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