Listen up haha,
Don't be concerned if you haven't had a girlfriend before you're 18. I'm sure so many people are in the same boat as you, there's no need to worry that you're "missing out" or you're gonna be seen as "uncool" cause you've never been in a dating relationship. People come and go but I know you'll find someone special one day and they'll be perfect for you and you'll be glad you never found anyone else cause they would never come close to what you feel for this partner.
Don't be worried, take your time and find the right person for you.
Good luck