How can I change my facebook unique URL?

[Trapped in The Wall]

My brother, as a prank, changed it to something rather embarrassing. Is there a way I can get facebook staff or someone to let me change it again?
You can only change it once. My brother changed it, and I can no longer revert it.

[Social]

Change Facebook URL-

1. Login to your Facebook account and click on the tab on the top right labelled as Account.
2. Now, click on Account Settings option.
3. There, click on the Settings tab and there look for the Username field.
4. Once you find it, you could spot a change option beside it.
5. Now, it will ask you for the new Facebook username.
6. Once you are done with it, click on Check Availability. And if that user name exists, it would ask you confirm the same and then it would show you your new Facebook URL.

I hope you will be agree with me.

Thanks
Social Aliens