i had rotator cuff syndrome last year after serving and playing volleyball for 20 minutes! ridiculous! anyway, it lasted for months at a time, where i couldn't raise my right arm into an "L" shape and all the way up.
finally after a few months knowing the pain wouldn't go away went to a doctor who gave me exercises and told me for a month straight to take 800 milligrams of ibuprofen 3 times a day. it helped a little but not much, eventually some 6 months after this all happened got a cortisone shot and eventually the pain has not totally subsided.
get some hardcore inflammatories and then do some very very light movement and if this doesn't help get a cortisone shot i guess.