Welcome to the wonderful world of parenting a twice-exceptional child! Many super smart kids who are neurodivergent, especially ADHD, go undiagnosed, because they can still function at normal levels. However, parents, and sometimes the kids, know that the kid is super smart, and are frustrated that they are underachieving, relative to how smart they are.
ADHD inattentive presentation is very easy to miss. We tend to think of ADHD as being associated with hyperactivity, and also expect really smart kids to be off in their own world a lot.
Our kid was only diagnosed as being ADHD (inattentive) in college because she also was dealing with anxiety, so between being smart, and assuming that many things were related to anxiety, even her therapist (who was great) missed it.
So you’re doing really well at getting a diagnosis in high school.
It took me over 50 years to finally get diagnosed…