Shoulder/chest issue

Last week, while doing pushups, I felt weakness on the area where the pec attaches to the shoulder during a pushup. Sort of a grating feeling. On the next pushup, the pec/shoulder hurt so bad it just gave out and I stopped. I iced it, took NSAI's, and rested it. I tried swimming 5 days later and stopped right away. The pec area is very sore in the area it attaches to the shoulder. Doesn't hurt all the time, just when the pec contracts. Any pressure which makes the pec engage, like using your arm to push on a table while standing up from a chair, makes it hurt. Seems like more of a pec injury than a shoulder injury, which I assume is a good thing. Anyone expereince anything like this before?