Patrick, hold that last thought in your post - that in a few years' time you will be the one who's laughing. I'd love to see her face when you turn up in your flash car to fix her computer system and then saunter off home at three o'clock just because you can!
It sounds as though the Jobcentre woman has one or two communication and/or equality issues and is maybe in need of some awareness training - perhaps you could suggest this to the centre manager when you're feeling a little more composed. No matter what your disability, you shouldn't have to feel disadvantaged by it.
Have you contacted the National Autistic Society? They may be able to give you some practical help, and I notice they have a benefits advice line you may be able to talk to:
http://www.autism.org.uk/nas/jsp/polopoly.jsp? d=1560
Just a final thought - my son and I thought for a few years that he had Aspergers, although there was never an official diagnosis. My friend's son, a little younger, also had it and he
was diagnosed. Turns out my son actually has OCD (different, but the symptoms are similar). He's now a very successful computer engineer. My friend's son has found his niche as a swimming instructor and fitness trainer and he's also doing brilliantly. You go for it, Patrick!