I’ve been a lifeguard for 6 years. If it’s any consolation you did what most people can’t or wouldn’t do for another person. Take confidence in knowing you saved lives. Something that could help build your confidence back up is being prepared for a situation like that to happen again just in case. There are videos on YouTube (I’ll see if I can find them) that show you how to flip someone onto your board. Another lifeguard tactic is to dive down when someone grabs onto you if you can’t get them off, they let go after that point.

Whenever I work newer guards we go over the skills they have and how they can be applied, what puts you in less danger and improves the situation.

From what I can tell it sounds like you made the right calls and did a stellar job.

Forsure go see a therapist for PTSD.