Ok so im going to see the doc first thing tomorrow, but in the meantime let's see what everyone here thinks. I was doing shrugs today, started off with 2 sets of 20 with 90lb dumbbells, then on my last set I moved up to 100lbs. On the second rep I heard a distinct pop followed by a sharp pain in the center of my upper back. Its been about 4 hours since it happened and the pain is still there. It hurts to look left, right, and down towards the floor. So far there are no signs of swelling, just pain. Does anyone have any ideas if this may be a torn muscle, pinched nerve, or worst? If so what are some good remedies to help the pain?