I cannot say exactly what it is because telling me that your shoulder hurts and a typed description of your pain isn't exactly detailed (there are many things inside the shoulder), but either way, whether its a sprain or the like, go to the doctor and get it checked. Believe me, few probably regret not going to the doctor like I do for being an fool and trying to "man up" and take the pain. If your muscle, tendons , ligaments have ripped, if they are not healed in the right way, you can end up having scar tissue. Spraining a joint is far worse then breaking bones, because when bones mend, they are stronger then before, but a sprain will permanently weaken that joint. It will never be as good as original. Check it out, don't be like me and have so many scar tissues (in my case on my ankle) that it feels like bumps and cracks whenever I move it.
