He used to be scared of hand driers, but is slowly becoming less bothered, at one point he wouldn’t even go in the toilet if there was one, now if it goes off, he doesn’t mind.
Ah. I was already thinking ADHD and sensory overload, but this is identical to my DD at that age.
So what might be happening with the instructions is that he can follow them at home, but nursery is simply too noisy for him to be able to do that there. I could not understand why, in Yr1, DD was unable to put on her coat or put her stuff in her bag at the end of the school day - but she was expected to do it in a corridor of 120 overtired children. Never happened. She's now diagnosed with ADHD, but inattentive rather than hyperactive.
If it's any consolation, the noise sensitivity tends to get better, but DD's ability to follow a series of instructions got worse, but is now improving ten years on.
I think it's easier to think of neurodiversity not so much as a series of discreet pockets - ASD, ADHD, dyspraxia - but as a wide-ranging cloud of symptoms and experiences, which includes high ability. So people may exist in a place on the cloud which is clearly labelled as ASD, but what the medical profession delightfully call co-morbidities are common and some people just have a mix of diversities. DD is borderline dyspraxia too, and is probably also dyscalculia as well (but this is masked by her abilities so she survives).
So the main advice I would have is just watch what he is doing and see how you can help him - it may, like the noise thing, take some thinking about to work out. And if he starts having bigger problems, then do look for a diagnosis. DD is very happy with hers (frankly, as a teenager, neurodiverse is quite cool).