Hoe could you miss the signals?

How could you have missed the signals?
When she's with you,
She smiles and giggles.

Boy, you know so little,
She's in the blues,
she's in love with you.
You know so little.

When she's planning to talk to you,
her heart runs a mile
from the thought of you.

Heart beating so hard,
but she had to hide,
this effect caused by you.

Butterflies fluttering in her heart,
when she's near you,
told you haven't I?
she's in love with you.

She keeps glancing at you,
oh, look! There she goes again!
she can't take her eyes off you,
she's hypnotized by you.

So what happens now,
depends on you,
Boy, make me proud,
tell her what's true.