When I was at university between 18-20, I did not dress well, did not socialise etc. Between 21-24 I started changing, dressing better, socialising etc. matured up. Was I too late? Most people do this at university between 18-21 years old.
No, it's never too late to become a better you. :)
Nope. I've met people who do that for the first time in their 50's.
No at all you still young and beautiful.