6 Year old son with Graves Disease

In September this year my son was diagnosed with Graves Disease. He ended his school year in the spring and began the school year this fall with just horrific behavior. He was having extreme outbursts, hitting, throwing, screaming in the classroom to the point where I was picking him up from school every day. In addition to that he has almost all the other symptoms of Graves. The unending appetite, the heat intolerance, sleep issues, weight gain and at 6 he’s taller than most kids 2-3 years older than him. His behavior got so out of control at school that he has now been removed from his home school and moved to another school in our district with the means to support him.
A few weeks into this school year and right after he changed schools I insisted to his Dr and his father that this is not our son, that I don’t think he can control his behavior and that I wanted his thyroid tested. We had bloodwork done and when we got the results it was obvious immediately that he was very, very hyperthyroid. His TSH level was >.01 and his T4 was 22. It helps that when my son was 3 years old I was diagnosed with Hashimoto’s and am familiar with reading the results.
After practically screaming and my son’s Pediatricians office when the nurse practitioner told me his levels were”Nothing to worry about”and that we “Didn’t need to do anything about it”, (She had to go through a review with the practice Dr’s after that) we were immediately sent to a wonderful Pediatric Endo in our area who confirmed that my son indeed has Graves Disease. We started him on 20mg of Methimazole right after his first appointment and after 2 months we can see some huge improvements in some of his symptoms.
At the same time he started seeing aPsychologist where he went through diagnostic testing for ADHD and ODD. Despite the Hyperthyroid diagnosis the Psychologist believes that we also have to contend with ADHD as well. I just don’t believe that he actually has ADHD and his dad thinks he can control his behavior.
I’ve given up on trying to make him understand that none of this is on purpose and that our son needs loving and supportive parents that understand that he is not himself right now and it will take time for him to return to normal. Our son is such a kind hearted, loving, imaginative and intelligent child that it kills me to see him struggle everyday with his emotions. It hurts even worse that I feel alone in understanding that he is being crippled by his thyroid and that none of this horrid behavior is our son’s choice.
I know that to be diagnosed with a thyroid disorder at such a young age is rare and that there is very little information on how Graves effects behavior in children, but I was hoping that there are other parents on this forum with young children that have Graves that have gone through or are going through the same struggle that we are. I know there is light at the end of the tunnel but right now it seems like someone had put a brick wall between us and that light.