Parent to Recently diagnosed 8yo asd son

Really struggling right now with my 8yo son. He was diagnosed early on in the year with level 1 high functioning asd which I know is at the lower end but is still being tested for his other quirks as I call them. Adhd came back negative and currently going through tourettes syndrome symptoms and a sleep referra.  I've been battling to get him seen and get help since he was 2/3. Only took me seriously 2 years ago and took 2 years to get a diagnosis so has been very stressful. Anyway recently his behaviour at school has been extreme, detentions, head teachers office, behaviour records etc. He's not like it at home, don't get me wrong he has his moments but is quickly managed and moved on. Ive tried all different ways of sorting it with him but it's seems nothing I'm doing is helping. He is at mainstream primary and they have a few things in place to assist him at school as per the requirements set out by his paediatrician but Im thinking he needs extra support perhaps? They wouldn't beable to do what I suspect he needs and his class already has 1 teacher 2 teaching assistants in his class. I'm new to all this and have been trying hard to research, rethink and change how I manage my son compared to his older sister.  Any advice would be appreciated, if any of this makes sense.