none of the symbols on my laptop were working when i was on facebook. <3, @, etc. so someone told me to press shift+alt+prtsc and now where theres supposed to be black, theres white, and where theres supposed to be white, theres black. and when i type, the backround is white, and so is the lettering, so i can' see what im typing. i tried pressing the button again a bunch of times, but it just turns it rainbow, or black and white. how do i change it back? and how do i get to make the <3 and @ symbols again? please help!!!!!!!!