HI, and welcome
It sounds like he cannot be soon too soon. I would call and try to make an appt with a Psychiatrist also, for therapy, meds, diagnosis etc.
I am curious as to how he is on meds with no diagnosis, since any co morbids could be worsened by ADHD meds, and he sounds like there are comorbids.
A child may HAVE ADHD, but it is not what they ARE. Never tell a child they ARE ADHD.