I"m a 250 day snowboarder and 250 day race motocrosser.
Shoulder separations and shoulder disclocation are prevelent in both sports.
The next big injury is broken collarbones.
You have a slight shoulder separation or tear. Relax your game for 2 months, you'll be fine.
I"ve had over 5 total separations, 2 disclocates, and 4 collarbone breaks.