I'm not stupid

What is the message for me?
I don't understand nothing
Speak all, speak something
I don't understand this

Speak, only speak
Don't scream
I'm not stupid
I have a idea

[chorus]
I don't know why
But in all my life
Nothing is right
Hey wait, speak with me

Why I care?
No, I don't care
I'm not stupid
I have a idea

Speak, only speak
Don't scream
You know I'm right
No, I don't care