Shoulder pain, can now only do *** stroke

Hi all, First, thanks for being there. I have right shoulder pain. This winter I foolishly took my first snowboard lesson, fell like 20 times. That week I had left wrist and shoulder pain, both healed. Now I've had right shoulder pain for over a month. I've rested, swam some. All I can do without pain is the *** stroke. The pain is on the back of my shoulder. I have a script for PT from my MD, I'd prefer working with informed swimmers instead. (lousy insurance, I pay for everything). I take napercin 2 twice a day. Pain is like a 7 or 8, start as soon as I do any other stroke, gets worse if I continue.m My strokes are pretty good. I practiced twice a week for 2000 yards. Until this I never had shoulder pain before, was so proud that doing all 4 strokes paid off. I had just started doing the 500 free (last 2 meets) but still practiced using all 4 strokes, just with some longer sets. I stretch a little before and after practice Any input is appreciated. I'm not very fast, soon to turn 59. I've swam forever, lifeguarded and taught through college. Debra with the Poopy Shoulder, Cleveland (and I get it, this is just a discussion forum)