Memory is not the same as recorded history. In humans, our memories change based on the strength of neural connections, as well as contextual events. Kurzgesagt's How Are Memories Stored Inside Your Brain? describes this with an example of seeing a crow and a squirrel fight over a nut, only for a mouse to steal it. The event is memorable because it's novel, but the more you think about it and retell it, the more that memory gets reinforced. Later, when you tell the story to friends in a funnier context, that new context can seep back into the memory itself. The next time you remember the fight, you may remember it as funnier and more absurd than it actually was.
I do this too, just in a much less cinematic way. A small joke in passing may build up over time to be hilarious as I tell the situation over and over again. Then, if I find the original meme or message a year or two later, I'll realize it wasn't as funny as I remembered.
I also remember a lot of details, but not always the right ones. Sometimes I can remember some extremely specific thing from years ago and completely forget something I was sure I'd remember later that afternoon. I'm trying to get better at recognizing the difference between "I'll remember this later" and "no, actually, write this down."
