A lot of the stuff you say sound like ADD/OCD, except one piece doesn't fit. The fact that you CAN concentrate on your music (and presumably not fidget while playing it), makes me strongly suspect that you DON'T have ADHD. ADHD is not selective. You can't have ADHD for things you don't like, but them have your symptoms disappear when you are doing something you enjoy. It just doesn't work that way.