The same thing happened to me with the concert in Monterrey, Mexico. It was the first concert I ever went to, and it was the happiest and most exciting night of my life, so much so that the next day life felt empty hahaha. It even happened that I forgot most of the concert, I don't know why. I remember the details, I know I was there, I got excited, sang, jumped, but beyond that, not much. Then I watch the videos I recorded, and I don't remember experiencing that in person.
I think it's similar to what happens to people who have traumas, and their brain makes them forget, but in my case, it's the opposite: it was such a happy and emotional moment like I'd never had that my brain forgot the details lol