A punk is a young troublemaker. If your elderly neighbor thinks of you as a young punk, he either thinks all kids are bad — or you did something that really disturbed him.
The Algonquin word for dust or ashes, ponk is the most likely root of punk, which originally described rotten wood used to start fires. That meaning is also found in the adjective form of punk, poor quality, or disposable. Facing long-term unemployment in 1970s London, kids invented punk rock and extreme styles of dress and hair to go along with it, because, in the words of a well-known punk song of the day, they felt they had no future.