Hi very confused

Hi I am new to this forum and would like some info from anyone who can help, my son is now 13 years old we have known he's been different from about 2, for the past 7 years we have had referrals and tests galore to find out what his problems are but have always come back as nothing because he was behaving well in school, at home and out and about he was a very different person, he was violent,abusive,threw tantrums,he doesn't like change and hates me tidying his room,he has dyslexia and is a type 1 diabetic, the past year he has hated going to school because he says he doesn't understand any of the lessons and has started to be verbally abusive to the teachers and has also lashed out at them , he has had so much time of as getting him to go is a battle as he gets himself so upset he starts banging his head against the wall, his secondary school has now said there is a problem and bothe them and I have had to fill in more questionnaires waiting is a nightmare we have waited 7 years already and don't know how much more I can take I just want him to have the help he deserves .