Laptop start-up help?

two days ago I left my laptop on hibernate and forgot about it for a while. When i realized that i left my computer on. When i clicked on a key start return to my username my screen stood pitch black so i turned it off but ever since its pitch black when i start it on u can hear its on. I want to know how can i get my computer back to normal and without losing any of my data

Meigury
May 2010