Voiced Pain

It started some time ago. This nagging voice that I hear, telling me I'm no good.
Talking loudly about all my mistakes.

But. No one can hear it but me....Why? WHY is it there. I don't know it. It's not my voice, it's not mine...I....I don't get it. Why is it telling me this horrible things.....why...why....why...why

And every Time it sepaks, my back hurts....it hurts so much I can't bear it, and it get worse and worse and worse with every time I hear this voice.

Am I going insane? Are the things it says true? Am I a monster?
What can I do..... what....what..what..what..what..what..what..what..what..what..what..what..

Stop it.....I need to stop it...but how....
....