hi ,,, i have been having a tightness in my right shoulder when i lift weights for quite a while..when it gets tight i rest it and it goes away,,,till last week... while doing bench press ..there was a weird feeling like inside my shoulder it didnt hurt bad but enough that i could not use it... it hurts to lift my arm above my head .. i can not perform one pushup... it feels week and aches .. can u give many ideas what may be going on?