Don't beat yourself up over this. When all is said and done, you are not responsible for their lives. The situation was a crap shoot. Like others, I would have asked him what he needed, given him some money, offered him a hot meal, but beyond that I too would have left him as I found him. Yes there are some good kids out there, that are just a little lost, tossed out of the family home and down on their luck, hoping for a better life, but many do have drug problems and mental health issues that make them dangerous. Your safety and well being should always be considered first.