Completely confused

I don't know if I am in the right place to post this but I am completely confused and lost by the whole progress. :(

my son is 9 and has also shown some behavioural problems growing up, he was a head banger till the age of 4 , fussy eater since the age of 2 and suffers from extreme anxiety. nursery and school have referred him to a number of different speech therapists but nothing. Got to the point 2 years ago I took him to Drs to discuss his problems and he soon put me in touch with a paedrician after a 9 month wait we got to see him who took one look at him and said he is in the wrong place and needs to be seen by a community paedrician as he believed ADHD was the right diagnoses for him. Another 7 months past and we got to see the community paedrician. He could tell me straight away that he was suffering from a sensory disorder and believed that mild Austism was more the right path of diagnoises for him but still had to carry out the ADHD assessment as that is what he was refered for. Since then another 3 months has passed we have had a meeting with a educational physiologist who did help me with some tips to try stop him having a melt down. But things just keep getting from bad to worst. He won't be alone ( even dragging to poor cat to the toilet with him ) he keeps getting attached to the stranges things ( we bought him a diary try help him but the picture on the front was too cute we couldn't write in it ). He is aggressive to his sister if she doesn't do as he says and then just recently he has been mentioning that he wants to die. It all come ahead on Friday when he held a knife up to his throat in the dinning hall and told the teacher he wanted to die :( I am heart broken. His school have managed to get in touch with a counsellor but still feel like I am left in limbo. He has in the past been fine at school but just recently they has been a incident every week which has caused him to become distressed. I try keep everything togther for him but as a single working mum with 2 children I am really starting to struggle just don't know what to do next :(. Please any help would be appreciated I feel like I can't do right for wrong