I recently did something like this….
I was diagnosed as a young child. I don’t remember an assessment and was never medicated. The coping mechanisms I was taught growing up were not contextualized as “for ADHD” they were just “the way things had to be done to get things done” As I grew into adulthood, I chocked up the behavioral differences to just the way different folks from different families learn to do things differently. Living as an normie, I started to question/forget my diagnosis.
So there I am, rediscovering that I might have ADHD as an adult from memes on the internet. When I mentioned it to my folks my mum emphatically reminded me that I absolutely had an official diagnosis X0 some years ago.