My first real kiss was at 18. It's not an uncommon thing either. My girlfriend had her first kiss at 18 as well... just so happened to be with me.
Some people are just uninterested or unpopular in high school, it's not until college or later in life that they begin to have a degree of success in initiating romantic relationships. It's the same way for some NT's, they're just better at it than we are but that doesn't always mean they're successful in scoring right out of high school.
_________________
"Yeah, so this one time, I tried playing poker with tarot cards... got a full house, and about four people died." ~ Unknown comedian
Happy New Year from WP's resident fortune-teller! May the cards be ever in your favor.