I don't even know for 100% sure I have it but the last time I tried to talk to a professional they basically just wrote me off because my grades were good as a kid, I understand part of the diagnostic criteria is symptoms presenting themselves in childhood but to be honest I got by just fine without studying or paying very much attention.
Does anyone have experience with this
There was some ADHD discussion in a thread earlier this week you might find helpful/interesting:
https://hexbear.net/post/213171
:this:
One of my long comments in that thread outlines the steps I took to get diagnosed with ADHD as an adult, despite having done well in school and being successful on paper