Does it work in safe mode. Just keep tapping F8 as the computer starts. Take the monitor cable from the computer and plug it into the laptop and see if it works. If so it could be your monitor needs renewing.
Or I suppose it could be a graphic card problem. best waiting until someone else can help. Obvious if wording comes up on the screen it will not be anything to do with that. graphics card is the most probable cause.
When it worked last night did you notice any corruption on the graphics? Any faint dotted squares or colours not quite right? Artifacts or textures not quite right? If so then I'd go with the graphics card failing.