Is it possible to develop double eyelids as you grow?

I'm 13, asian and over 5 days I've gone from single to double eyelids. It started with my right eye and then the left. I know its not because I'm tired or a just-woke-up-eyes kinda thing, because when I run a finger down my eyelid to get it back to single because it feels slightly uncomfortable, and usually it works, but it flips back to double. So far its been staying double. I asked my dad, who's a doctor, if its possible to develop it while growing up and he said yes, for some people, but I'm not so sure.