i went a year after i did it my first time before i popped mine out again (don't know the actual terminology for what I did, the doctor told me to have a surgical prep sheet filled out the next time I went to see him so I haven't gone back) but now it happens all the time. Most of the time now for me its just an out and in quick thing that hurts but I'm fine after a little, every once and a while I cant move my arm for a while. I dont really want to go in for surgery because I've heard that if you mess it up again after the surgery it is a lot more painful so I'm fine sticking it out.
And to the dude that says he subconsciously protects his shoulder, I've noticed that I almost always have my arm in the position that it was in a sling and I do the same thing when I fall.
i would rather not talk about penis size, mine is very short that is why i have to build a fast car to try and make it bigger.