I pulled my laptop apart, now screen is black

Hi guys,

I pulled my toshiba p105 laptop apart in an attempt to clean my keyboard, but didnt get it completely apart as I could not figure out how to undo a screw under the keyboard. When I put it back together and turned it on everything else works except for the screen (its just black, like its powered off). I can even swipe my thumb print and it enters windows, just wontdisplay it. What have I done?
Thanks!