Pressing arrows flips computer screen

Hello,

Was wiping dust of my keyboard and pressed pretty much all the buttons. Next time I go on laptop screen has flipped. No problem I thought, just ctrl+alt+up. Didn't work. shift+alt+up. Didn't work. Finally I figure out how to flip the screen back using the control settings, and then I pressed the down arrow and it did it again.

So conclusion, is seems that the left and down arrows keep flipping the screen however pressing the up will not reverse this. I can use the control panel to flip it back but this is annoying and frustrating. What do I need to do to stop the arrows automatically doing this?

Cheers