I don’t mind helping you out.
Speaking as A 19 year-old kid with ADHD:
Anxiety is a possibility, but when ADHD is added to it, these two are not mutually exclusive usually. When dealing with us (kids especially), anxiety and ADHD go hand-in-hand, because anxiety is normally a linked result of ADHD.
Because of how our brains are wired, kids with ADHD are normally a few years behind other kids in terms of their mental & emotional development. Unfortunately, because we are often oblivious to how our behavior impacts ourselves & others, we fail to fully grasp when something we do is inappropriate for the situation.
It’s the equivalent to touching a hot stove & getting burned for the first time. Sure it hurt, but until we understand WHY and WHEN to NOT touch a hot stove, we’ll do it again out of ignorance because we can’t recall the first time we did it.
So I would say that the immaturity (and regression) your kid is displaying is completely normal because he has ADHD.
Hopefully this helps,
-Kendall Boults Jr.