I dislocated my shoulder twice. I was a heavy kid so trying to do that thing where someone holds your legs while you walk with your arms isn't a good idea. Just know that i felt something was out of place and i clenched my arm to make sure it didn't move.
After a minute i tried rolling my shoulder and somehow managed to put it back into place. From there i thought, crisis averted, but i stupidly thought it was a good idea to play Frisbee a few seconds later. I took the Frisbee with my bad arm and just as I made the motion to launch the disk, I ended up dislocating my shoulder again.
I clenched my shoulder again and went to my teacher to tell him "i dislocated my shoulder". He asked me, "are you sure?" I looked at my arm and said, "I'm... pretty sure." A fellow student helped me get to the nurse but she wasn't there. While i waited i tried to adjust my posture cause my back was killing me, and i somehow managed to put my shoulder back in place again.
In the end, they didn't have any arm supports so they just took a really long bandage and wrapped it around my stomach and back to keep my arm in place. Moral of the story, don't do anything with a dislocated shoulder after you put it back into place.