Man, it sounds like you might have some ugly stuff, like a rotor cuff tear along with other things. Git that MRI done, and then you better stand by for some surgery.
Don't sweat it, though. The stuff they give you for surgery is GOOOOOOOOOOOOOOOOOOOOD shit, man. I been there, and it's better'n any you buy on eth streets. Just watch the vicodin or oxycontin afterward. You'll need it, but don't let it rule you, ya know?