What's wrong with my samsung nexus s?

I dropped my samsung nexus s 4g and now my screen is dead. The phone charges (charge light is on) and will turn on but the screen is black. The menu keys are touch and its all one screen. The menu keys light up but nothing elce does. The screen is still touch sensitive tho. I have a pattern lock and the phone vibrates if you get the pattern wrong. When I run my finger on the screen where the pattern dots would be it it still vibrates if the pattern is wrong. My notification alert also still goes off for facebook and email and that stuff. I can't figure out what is wrong with it or what I need to replace. Any help?