LOL don't feel too bad bro...remember, I carry a 9mm at work.
And I got ya beat on the BB gun story, too...I was about the same age, 13 or 14, and got blasted point-blank with a CO2 powered Daisy 454 autoloader...went right through my shorts, and about 2 inches into my right thigh. That BB is still in my leg to this day! The docs didn't feel that it was worth messing with the muscle tissue and whatnot trying to dig it out, and it wasn't/isn't hurting anything so they left it alone.
I personally feel that 9mm is the perfect choice for concealed carry. Not much recoil so it's easy to shoot accurately with, and less risk of collateral damage/overpenetration.
But, with the right JHP round, the person you hit WILL rethink their actions in a hurry. Might not kill them, but at that point, killing the person isn't your concern...you shoot to stop the threat. If that means the person dies, so be it. At that point, it's in the hands of the man upstairs.
I'm fairly certain though that if you do your part, the bullet will hold up it's end of the bargain...9mm or not.