Every teen is different, whether they are NT or not.
Some kids may go through a cocky phase at 13, but others my go through the same phase at 16, or they may never have a cocky phase.
For 15-17 in general, I would say most people are increasingly independent, and they probably think they are more independent than they actually are. They try to act confident and cool, but are often very self-conscious. They may get upset easily if they they they have been insulted or rejected. Their personalities, interests, values, and goals may change quickly and change often because they are trying to find their own identity and they keep changing their mind about who they want to be. Most of them are increasingly interested in dating, romance, etc., and they may have longer, more stable relationships than 13-14 year-olds, but their relationships are still fairly unstable most of the time.
Once again, these are generalizations. Not all teens with be like this. Some teens may go through these phases earlier or later. Differences might be caused by neurological differences (like AS), personality differences, or life circumstances.
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Your Aspie score: 120 of 200 ; Your neurotypical (non-autistic) score: 90 of 200
You seem to have both Aspie and neurotypical traits
Self-DX: Extreme Introvert, possibly with ADHD-Primarily Inattentive; Official DX: Generalized Anxiety Disorder