There is definitely a difference between ADHD not sitting still and normal kid not sitting still.
My kid was continuously falling off his chair because he was creating a tension bridge between his chest on the edge of the table and his feet on the seat of his chair.
It was driving his kindergarten teacher crazy lol.
Related: it was a 15 minute doctor visit for us, but both me and my wife have ADHD so the doctor looked at the survey and said "boy howdy, I think you guys know what you are talking about"