When my adult daughter was diagnosed with adhd and she helped to frame for me how the symptoms actually manifest and apply to me in real life - I couldn't do this just by looking at a list of symptoms.
I didn't class myself as forgetful, I was literally forgetting how forgetful I am! But she remembered all the times I've had to get a locksmith for forgetting my keys and that I have to have a cross body strap handbag or I will forget it, and that I'm always forgetting food in the oven, and once forgot to put the chicken in a chicken curry
I didn't class myself as often late, but this is because I way overcompensate for this by being way too early now, after all the hideous experiences of being late in the past
Then I realised all the other things, like never finishing a project or an art/craft thing I was doing, all the absent minded mishaps with drinks (like pouring hot kettle water directly into the sugar or tea jar) - was inattentiveness
I often reply to a post having missed a key detail, could have done it again now for all I know
If I get a letter and both sides are printed on, I'll never know, never check the back
I then presumed I was primarily inattentive type, but my daughter also knew that small things can be hyperactivity - leg bouncing, nail and skin picking, racing thoughts, fiddling with hair, fidgeting, all of which are me constantly
I started thinking deeply about my childhood and found some old school reports. It was a hard read. teachers clearly knew there was more in me, but not how to unlock it - they thought I needed to apply myself, try harder, make an effort - constant low effort scores. I loved school and was already trying my hardest. I also got in trouble a lot for losing or forgetting my pe kit, forgetting letters home, when photo days were, non uniform days etc.
I was also incredibly hyperactive and did every sports after school club and was on every team. If I wasn't doing that I was climbing trees or training for athletics or gymnastics, or in a weekend dance club, or doing my cindy crawford workout video in my room. When I got to high school, I would walk 5 miles instead of getting the bus, barely sleep and get up early to do it, then walk back as well
I got my official diagnosis a year after she did. Both of us have combined type ADHD
It's so obvious now its ridiculous
Oh and I also recognised all this in my mum, and she's now on the road to diagnosis as well. When ND is all you've ever known, you think it's NT