Do I look 15?

So I went to my friend's child's birthday party a few days ago. He just turned 2 and is one of the cutest kids out there. While I was watching him open presents, this weird 14 year-old kid started talking to me about Yu-Gi-Oh and Magic cards, and why he likes magic cards better than Yu-Gi-Oh. So I was humoring him for a while, then he asked me, "So what grade are you in?" And I couldn't hide my shock at the question.
"What GRADE am I in?! I'm 26."
"Oh, you don't seem that old, you seem more like 14 or 15."
Awesome.
Then a woman who was at the party told me that it was because I look "jovial" and smile a lot, and I "look too happy to be 26." I spent the rest of the party building castles and cities out of foam blocks and playing princesses with her 5 and 6 year-old daughters.