Don't worry OP there is someone out there for you!

be patient and try your best. you can!

Just because he did it earlier, doesn't mean you won't do it better.

I guess you taught him well

I had this happen to me, a number of times. Honestly, it might be disheartening now, but when you find someone you care about, and who cares about you, it won't matter, the wait will be worth it. I also found that being single I was better able to think about what I wanted and understand what I was looking for. Seeing everyone else have relationships before I did, I knew how to better handle relationship problems. Dating early and having lots of relationships is fine, but being single is fine too. It isn't a race, and you shouldn't think less of yourself just cause someone younger happened to get a relationship before you. If you define yourself by a relationship, or whether you're in one, you'll never be truly happy and you'll set yourself up for disappointment.

I've babysat kids three years younger. it's not that weird.

Ask him for some tips. 'Hey, remember when I used to change your diaper and give you baths? You kind of owe me. Can you help me get a gf?!'

I didn't realize it was a race...

Well go ahead and beat him at his own game!

maybe he can now teach you how to pick up a girl.