Looked like ADHD/ODD. Here are some characteristics my son had. I may also add that high functioning autism is easy to miss in the early years and more obvious later on:
1/speech delay
2/memorized television shows
3/hated transitions
4/tantrums, headbanging, scratching face
5/played by running around with kids, not with actually interacting with them, but he was friendly, smiled, and pointed
6/loved letters and numbers and memorized them early.
7/fussy about food, textures, noise (covered ears)
8/liked to play with lightswitches, but did not really play with toys and didn't have much of an imagination (except when he copied his television shows)
9/Seemed very advanced in some areas and way behind in others
10/pottied late, especially poop (5 years old)
11/very hyperactive and needed Special Education to help him in school
12/talked to himself in his room
13/Would sing in his classroom at inappropriate times.
14/Seemed detached, very spacy at times. Other times seemed very focused and with it.
15/Went ballistic if he had to stop one activity and start another one.
I"m sure there are other things that I"m forgetting just now. Every single child on the autism spectrum is different. The biggest factor is cluelessness about socializing correctly. The kids may go up to other kids and intrude, babbling nonstop about thier obsessions. They do not do well in a give-and-take conversation. They do not understand social rules and norms. Some with Aspergers are VERY precocious, rather than speech delayed, and tend to monologue, sounding like "Little Professors." Most have an obsession that fascinates them, but bores other people, espescially the degree of their obsession. Dinosaurs, weather, radios...can be anything. They like concrete stuff so many are very into computers.
Hope this helped