15 yo son just been diagnosed with autism and refuses help

Hi, my 15 yo son has just been diagnosed with autism and previous to this has missed nearly all of last year (Y10) due to anxiety and depression. He was due to start back in Y11 last week with minimal support in place but 2 days before term started he said he didn't want anything extra as he just wanted everything to go back to 'normal'. Couldn't get him in on first day back, he said he wanted to change school to a smaller one. Two days later he then stated he didn't want to change school! So tried to get him in but he refiused to get out of the car so head teacher coaxed him in for one lesson. Next day couldn't get him out of bed, tried to persuade him and it ended up with a massive , angry/aggressive meltdown which involved emergency services and us turning up at CAMHS (where he has been going for the last year). Our problem is he just won't accept any help as he just wants things to be normal yet he can't get to school because he doesn't like 'the people and the noise'. At a loss at what to do. Can any one help?