I think in your case, some people got mad because the rest of their group arrived, and that's their own fault for not communicating with the other players around. I doubt your 'mistake' will be remembered by anyone 15 minutes later. Maybe the etiquette varies by server for hunts, but on Faerie, there doesn't seem to be a formal process about when to engage a hunt... you just wait a reasonable amount of time for people to show up, then someone leeroys it, and the mark dies in 10 seconds. That sounds like what you did! When in doubt, you can just wait and eventually someone else will pull it or ask for it to be pulled.

For hunts, there will be several hunt linkshells with 50+ people in each. They'll often report sightings and form groups from there to engage the hunts. You probably just pulled before one of those groups fully arrived, so the other members got miffed. Not your fault!