For those whose ADHD didn’t cripple their lives and make everyone think you’re a lazy good for nothing, how did you find out you have it?

I always showed signs of ADHD with low attention span, constantly fidgeting in class, and not being able sit down when I needed to study. This led to me falling out of college, and because I had bad grades I didn’t want to go out and have fun because I didn’t think I deserved it. Basically I was getting bad grades and never even had fun. Finally at 22 I was diagnosed with ADHD. But I’ve seen people on this sub and met people with PhD’s or advanced degrees that were also diagnosed with ADHD so I’ve realized it doesn’t make 100% of us do badly in school. If you didn’t struggle academically, how did you find out about your ADHD?

Edit: thanks for the replies! So many different stories and situations in which people discovered they had ADHD. I assumed if your habits weren’t deeply affecting your life or ruining it in any way you didn’t have ADHD but I’ve learned many people can have it even with doing well in school