Will I be on a watchlist after watching this?
What you probably want to ask is 'how big is the watchlist'.
That's the evil nature of them. You don't know how you ended up on one (or how many). You don't even know if you're on one. And if you did, there's no process for getting off it.
There was a story several years ago about how one of the US states (Rhode Island??) was dumping everyone convicted of a felony into the national terrorism watchlist. And didn't care, because {shrug} they're felons.