Harmless prank goes wrong.

Typing this makes me want to die. Me and my brother were playing football (soccer) together and so far the day was going great. Two of my brothers friends came out and decided to join us. After a few minutes we got bored and decided to play a game of knocky knocky nine doors (ding-dong ditch in america). For those who are not familiar this involves going up to random peoples doors knocking on them and then running away and is typically played by young children. Eventually it was my brothers job to knock on someones door. Now before I go any further there is something I must establish. I was 15 years old at the time, my brother was 11 and his friends were 12 and 9. Before the NSA kicks my door in I do not make a habit of hanging out with children way younger than me I was simply bored and had nothing to do. Back to the story. So my brother knocks on this persons door and we take a step back in anticipation to run away however no one answers, he knocks a second time no answer and after the third knock we were confused. We knew someone was in because the lights were on but no one was answering. I decided i would walk around the corner to see if the person had though the knocks were coming from their front door. I was Right. A man still in his PJ's asks me if a I saw some kids knock on his door. I am socially awkward as fuck and hate confrontation. So my brain decided the best option would be to run away. Bearing in mind this guy just thinks Im a random passer by. The guy follows me and asks me where Im going. I didn't answer and kept. The guy stopped following me and just watch me as I ran for no reason.. I still have no idea why I ran. This man had no clue who I was and I could have just told him I hadn't seen anyone. This happened a year ago but I still have ptsd flashbacks to it to this very day.