"
she thinks I'm cool,
I ripped my jeans and dropped out of school,
I followed her 'round the town but she thinks that I'm a weirdo now
Sitting here at home, it's
He is basically just trying to change himself so she can like him but its not working. He's trying for the bad boy look that most girls fall for. When it says "I pierced my lip so she thinks I'm cool" he pierced his lips cause most girls find piercings attractive. And he's implying that because he is following her around the town trying to know her, she thinks that he is a stalker and really weird. Its just saying he is trying to get her attention but its not working.