Those are autistic traits, yes. But they can be traits of other things, too.
What I am reading, though, is that you have some traits that cause hindrances in your life, like when you stay home because you can't be early to something. And that is cause to go to a doctor and get an evaluation. You may want to mention the possibility of autism to them; tell them that you had a friend with Asperger's, and that you have many of the same traits. It's kind of surprising that this wasn't caught earlier; being 17 now, possibly you were simply quiet enough not to cause problems at school--it's the loud, disruptive autistic kids who are most often diagnosed, after all.
Regarding emotional expression: Some autistic people have a flat affect (this would be your friend's tendency not to express emotions he felt); others do not. Some have the problem that I have, which is being simply unable to inhibit emotional expression, so that every emotion is expressed in a very obvious, dramatic way--that can lead people to think you are terrified when you are actually just anxious, or homicidal when you are actually just annoyed, or manic when you are actually just happy. I have had to tell therapists multiple times that I over-express emotion; but they still don't seem to realize that I am not actually suicidally depressed when I express sadness... Oddly enough, the only times I have had true flat affect was during episodes of major depression, when I was in such danger!
In any event, emotional expression for autistic people can run the gamut from nearly absent to full-on dramatics. The common trend seems to be to have trouble expressing emotion so that other people can read it accurately--whether that means too much, not enough, or just sending signals that people read as the wrong emotion entirely.