I wrote here a while back, thinking that DS may have AS, ADHD.
I would say from your description that there are some 'red flags' there for ASD - possibly Aspergers - and that this is worth following up. Your therapist is not qualified to diagnose ASD or Asperger's so you need to talk to someone who is. And you also need to be aware that at this stage you might not get any 'clear' or definitive answers or diagnosis. Several of us here on the board have had a long and sometime frustrating path to diagnosis because it can be very difficult to diagnose ASD/Aspergers in young children. We had red flags for something at age 3 but it wasn't until DS was 8 and we'd been down a lot of red-herring routes that we got the right diagnosis.
Although getting the 'right' diagnosis can be very helpful ( and the 'wrong' one very unhelpful!), I think it's also important to say that at most stages it is identifying what is the most appropriate help and support for your child, rather than the diagnosis itself, that is the key. Medication won't help if it is not something that medication can 'solve', but it will help if it is. Similarly, techniques that you can use with ADHD kids might not work on ASD kids, and vice versa. Finding the right combination of help, support, therapy etc can be tricky, but it is worth taking time over it.
Kirsty, mum to Euan (12, Aspergers Syndrome) Rohan (7, NT) and Maeve (4, NT)
"My definition of housework is to sweep the room with a glance"
Follow my blog on http://mumsnet.com/blogs/kirsteinr/
Thank you Kirsty.