OP, I am absolutely not saying your DS has ASD or anything like that, but I would just like to clarify about what you've said re ASD mainly because alot of people don't understand about it, or what to look out for.
I don't want to hijack this thread, but I have to just say about this because I think its too important not to. There are alot of children who miss out on help because people don't recognise the issues and many desperate parents who think they are 'bad parents' because they don't understand why their child is behaving like that.
Alot of people have quite set and simplistic ideas of what they think ASD looks like i.e. lack of empathy, emotion etc. It really depends on what type of ASD a child has. Someone with classic autism will behave very differently from a child with say Aspergers or ADHD. And, it also is dependant on how far along (the degree) the spectrum that child is. Also a child may well have more than one type, so will exhibit different combined aspects of each. My youngest was eventually diagnosed with DAMP, a completely made up term recognised only in Sweden and a couple of places in UK (its basically a good way for authorities to avoid doing anything to help the parents and they don't get a statement). DAMP (Deficit Attention Motor Perception) with aspects of ADHD and Dyspraxia - so he wasn't bad enough or straight forward enough to warrant a diagnosis of one or the other.
We didn't know what we were looking at before he was diagnosed because he didn't fit in with what we thought ASD was. My son is extremely intelligent (even from an early age), extremely imaginative, has excellent knowledge, debating and language skills (beyond his age - which was especially noticeable when comparing to other children when he was in pre-school/Foundation stage), understood and seemed to empathize with and sensitive to the feelings of others, could focus and be absorbed with a toy, game or project he was interested in. But would have extremes of overwhelming emotion that he just couldn't handle which meant that he had terrible extremes of behaviour, mood swings etc, as well as short term memory issues and some physical motor things which we didn't notice or understand until we knew what we were dealing with. Would you think that a Pre-School/Foundation child who could talk knowledgeably about life in WWII France, but consistently didn't bring the hat and the toy you asked him to fetch from his room multiple times and always ended up doing something else, as a child who is ignoring, defying, being rude to you etc etc? Or would you think by saying you wanted a hat and a toy his short term memory wasn't processing the words in the right way and one or both of the objects were 'disappearing' by the time he got to his room??? ASD doesn't always look like you think.
I say this as my son wasn't diagnosed until he was in Year 1 of Primary. And I also think he only got picked up on because his class teacher was the SENCO and it was in her best interests to get him, and the other boy in her class who was the same diagnosed. We had a bad experience with his first primary school. Alot of the time schools do not want to really know because it ends up costing them money if a child is diagnosed, even if they aren't statemented. We spent the first few years up to that point thinking we were bad parents who just couldn't handle what was going on. Getting that diagnosis was terrible - it felt like we were almost grieving for him, but it also gave us a massive sense of relief- we weren't bad parents and we weren't going crazy. I always think knowledge is power. It can only help to know what you are dealing with.
Sorry to say all this on this thread. And OP I'm definitely not saying your son is on autistic spectrum.