you stand your ground and fight not for nothing so he dosen't fuck u up when ur in the neighborhood not paying attention to whose around you. or he could possibly follow u back to your place and break in and mess whoever is there up. so in that situation at the gas station you should of grabbed some glass bottles busted his head, if u didn't wanna get close then throw a few. then when the cops show up after he's fucked up if they do u claim self defense because he was following and threating u with a knife. he goes to jail all fucked up and u go about ur way. for running he now knows your weak chances are if he sees you again he will pick u as an easy target. for u fucking him up if u didn't get self defense for him threating u with a knife your sentence would be light because ur a minor.