running down the sidewalk in the opposite direction to me and my friend:
Simply yelling "heads up!" to make sure I see you coming at me is generally enough to make sure you don't crash into someone. You saw me look up and move aside to let you by. What's NOT necessary is to whack me on the shoulder and physically shove me out of the way as you run past.
I hope you fell and scraped your knees, dillhole.
(Seriously, who does that?!)