What's normal anyway?

I have been doing some counseling on the side lately and I currently have a little boy who has explosive temper tantrums. He's been diagnosed with Asperger's disorder, which if you don't know what that is, it's a mild type of Autism. As I sat and watched this very vivacious three year old play computer games (which I am certain my three year would have trouble figuring this out), I wondered - what parts of his behaviors are due to his "disorder" and what parts are just being a typical three year old boy. His parents described him getting upset when he doesn't get his way, not wanting to eat what they give him, throwing fits in the grocery store, flailing his arms and legs when he gets mad, etc. As I listened I began to wonder if I should test my son for Asperger's, because their behaviors are quite similar? Don't get me wrong - I am sure he is quite a handful for his parents, and I don't want to assume I know what they are going through, but I did have to wonder - is it healthy to assume all of what he does is due to this "label" he's been given? Will he now operate under the label "Asperger's" for the rest of his life? What if he hadn't been diagnosed? What if his parents learned to how to respond and deal with his behaviors under the assumption that he was just a challenge? I'm just throwing these thoughts out there today. I sometimes just think that we have become accustom to labeling children because we want a reason for every single problem they might have. Maybe there isn't a reason, maybe God is just trying to teach us something, or maybe it is just the way the kid is - no reason - just a challenge. Anyone else have any thoughts?