Great story: you really capture what it feels like to be a teenager, when everything is new, when everything seems both infinitely possible and not at all. I really like your Sam here - I found particularly poignant the part where she wishes she were born a boy, because everything would be different (when we know it wasn't).

I like Dean, too, through this Sam's eyes, gallant and annoying and alluring, both brother and stranger in one.

Man, this was good! I really liked it a lot.