I found it useful to review my performance and all related to it after a competition to see what went well, what needs improving and what I have learned from that. It could be interesting and fun to have a thread with these experiences, whether serious or humorous.

Agree on the stamina.

And coffee is not food!

I can second the scheduling flights back to a rather later time than the estimated competition end, especially if you have not confirmed that the particular competition always runs on time. We had to leave for our flight before going for the finals in one of the events, though the flight was at a lot later time than the estimated competition end. 
Lesson learned for the next time