SUDO goof-up

[Lee]

I tried running firefox running it threw a root terminal session.(Don't
ask).
 I did this command
 sudo firefox
And now when I try to launch firefox in user mode I get this pop-up
window and it says: in a little title bar at the top of the window:
Gecko and then in the pane
              title="mainWindow. title;"
 --------------------^
So how can I reverse this goof-up? Thanks in advance.
And by the way i have really enjoyed this distro it's great!