I think some socially created ideas like "teen years" are not very useful; like deciding that all 20-somethings have to get married and start families and careers, etc. It's all just "fashion". One did not have teens back a couple hundred years ago; or childhood before that, etc. I did not consider myself grown up until I hit 39/40.

Comparing myself with others just got me more confused for a longer period of time. If I could do it all again I'd pay attention to myself and what I wanted a whole lot sooner.