Taylor Swift's 4th single from her sophomore album Fearless.

I do not own this video.

lyrics:

You take a deep breath and you walk through the doors
It's the morning of your very first day
And you say hi to your friends you ain't seen in a while
Try and stay out of everybody's way

It's your freshman year and you're gonna be here
For the next four years in this town
Hoping one of those senior boys will wink at you and say
"You know, I haven't seen you around before"

'Cause when you're fifteen and somebody tells you they love you
You're gonna believe them
And when you're fifteen feeling like there's nothing to figure out
Well, count to ten, take it in
This is life before you know who you're gonna be
Fifteen

You sit in class next to a redhead named Abigail
And soon enough you're best friends
Laughing at the other girls who think they're so cool
We'll be outta here as soon as we can

And then you're on your very first date and he's got a car
And you're feeling like flying
And you're momma's waiting up and you're thinking he's the one
And you're dancing 'round your room when the night ends
When the night ends

'Cause when you're fifteen and somebody tells you they love you
You're gonna believe them
When you're fifteen and your first kiss
Makes your head spin 'round
But in your life you'll do things greater than
Dating the boy on the football team
But I didn't know it at fifteen

When all you wanted was to be wanted
Wish you could go back and tell yourself what you know now

Back then I swore I was gonna marry him someday
But I realized some bigger dreams of mine
And Abigail gave everything she had to a boy
Who changed his mind and we both cried

'Cause when you're fifteen and somebody tells you they love you
You're gonna believe them
And when you're fifteen, don't forget to look before you fall
I've found time can heal most anything
And you just might find who you're supposed to be
I didn't know who I was supposed to be at fifteen (less info)