“Shadow Boxing When I Heard You On The Radio”

Alright, I unfortunately have another bizarre experience to recount and I’d like to know what you would have done in my place.  So on Sat. around 2ish I’m walking down 14th Street just north of U Street when I pause to write down some notes in my pad.  When I look up there is a kid probably around 15 or 16 who is shadow boxing right at me.  He is taking punches that are landing very close to my head and body.  I’m terribly confused at this point, so I’m looking quizzically at him trying to ascertain whether he is kidding around or just showing off for his friends.  But no, he is by himself and doesn’t make the slightest smile or give me any other indication that he is kidding.  So I continue to stare for a second, and he returns the stare with some more shadow punches and a very menacing look.  So finally, I decide just to keep walking.  But what I really wanted to do, was go right up in his face and say “What the fuck are you doing?” or “Do you have a problem with me?”  Or something like that.  But as usual, I grit my teeth and shake my head and just keep walking.  So what would you have done?