Hurt Shoulder

My right shoulder has been hurting me for about 2 months now. It's alternating the way I sleep (I have to have my right arm down by my side), so I decided it was time to go to the Doctor. The dumb thing is I'm not sure how I hurt it. Deni made me an appointment with the same Dr that just did my Dad's shoulder surgery. He took x-rays, which he couldn't see anything, and then suggested that I get an MRI, so next week, I'll be going in for an MRI to see if we can find out what's wrong with my shoulder.