Yes, provision depends on area and budget but mainly on how much of a gobby pain in the arse you are! You have to fight, fight and fight some more, sadly. They HAVE to meet your childs needs. In theory. But in reality they will try to give you as little as they can get away with, so it's up to you to push them for every scrap.
For someone with a child with asd, the attachment of that label is a good thing - because you wave it around to get support for them!
I'm not an expert in autism, only an expert in my 2 kids , but I know that if your parental alarms are going off, you need to get on in there and never take piss off for an answer!
If you do feel there is something, go to your gp/hv well prepared. Go with a list of things that cause you concern, things that between them cover each of the 3 sections (see my earlier post about the triad)
Most importantly, keep an open mind. There may or may not be an issue, all you are seeking atm is an opinion. Don't work yourself up.