Just moved home - 5 year old having meltdowns, hitting and biting.

Hi,

Just a bit of background, My son was diagnosed as autistic aged 2, he has no means of communication, he uses hand pulling to get drinks/food but apart from that completely non verbal. He also doesn't follow simple instructions. 

So we just moved to a new property 3 weeks ago, a week after he started his new specialist school. He doesn't usually show distress transitioning or making any new changes. The start of his new school went well, showed no distress etc. Then we moved a week after he started school, that week the school called me as he was showing signs of distress, intense crying and screaming. I went and got him from school and this continued on and off every couple of days... to the point that I have taken him to hospital 3 times thinking he was in pain but that was ruled out (as far as it can be as he is unable to tell you whether he is in pain of course).

2 weeks on from this his tantrums have got worse, he physically attacks me and bites me and hits things etc which he has never done before. This happens at least a couple of times a day now  

I just wondered if anyone with a non verbal autistic child has ever moved home and experienced anything like this and how long did your child show distress for?  I was hoping things would have got better by now. Also any advise on what to do when he is attacking me? At the moment I am trying to keep him at arms length but I'm struggling with that. He hit me in the mouth yesterday and I had to go sit in my room and hold the door shut until he calmed down!! 

Thanks in advance to any advice!!