Display icon missing on menu bar and not in display settings

[handre2]

My display icon on the menu bar on my MBP seemed to have disappeared. Its also not under my display options where I should be able to tick it to show in the menu bar.

I suspect I messed it up with some or other terminal command I added.
Is there any way for me to restore it?

 

[mgartner0622]

What operating system are you running? I'm not sure how the displays work in Mountain Lion, but on my Mac Mini it won't show the display icon or give the option to until 2 displays are connected.