Please forgive me if I don't use all the correct terms, I have been lurking for a while, but not plucked up courage to post until now.
Have long suspected DS1 (4.5 just started reception p/t) has HFA (and possible ADHD thrown in). We seem to have good and bad phases and whenever we are in a bad phase I wonder if DS1 would benefit from a diagnosis (feel guilty for burying head in the sand previously 
). Then it passes and I think we are best managing it ourselves.
After reading much about the length of time it takes to get a diagnosis (and then seeing what little is often done to support people) I am left wondering whether it is even worth getting a diagnosis at all.
It was much easier for me to prop him up socially and explain emotions etc. to him as a pre-schooler. Now that DS1 has started in reception at a new school, do I inform the teachers of my suspicions or wait for the teachers to initiate it if and when they notice a problem? I haven't spoken to the new teacher at all yet. We are having a major bad phase at home since he started school part-time.
I am really worried about doing the wrong thing and want him to have a 'normal' school experience. He comes over as happy and clever, but also a bit odd and disruptive. He is so borderline that all of his grandparents think he is just a normal 'geek' who is clever and a bit obsessive.
FWIW the problem behaviours are obsessive and repetitive play, not listening or responding to direct questions, talking at people but not replying, not understanding social rules (but is learning them by memory), very limited diet, superb memory, really high energy levels, trouble getting off to sleep (rocks to sleep), sensitivity to smell and some lights.
I would really appreciate and advice, experiences or suggestions at all 
.