This song is about a particular break up with a girl. Mike is still friends with her, and he still wants to be back together with her. “its your last chance to change things” is sort of him telling either himself or her that this is it, its his last chance to get back together with her.
Implicatio...
It's your last chance to change things
I know you've been getting by
But I saw you at the party without
A drink in hand
Or a word in mouth
Nothin' to do
Or talk about
Poor skinny fat kid
Without any interest in
Making friends
It's not easy being…
Oh, I know...
It's not easy being…
Uh oh go
Oh no, go on
Oh go, I know
Go on