My Dell Inspiron N5110 screen goes blank / white immediately after I turn it on

I leaved the computer on a chair, my little cousin I think that throw it to the floor accidentaly, but im not sure.

The computer goes blank immediately after I turn it on without making any kind of sound. No Dell logo and no other thing is shown, it only goes immediately white.

And after ~ 1 minute it makes that windows sound that is heard when before entering to the accounts / sessions.

When I connect it to an external monitor and press FN + F1 it asks me to choose between resuming windows or safe mode. If I choose to start normally it show the windows logo loading and then automatically switches to the laptop screen, the monitor goes black and the laptop white again. But if I choose the safe mode it works.

Then I runned that test and was all ok, I even made the 30 minutes test too.

I dont know what it is, but if it works in safe mode it shouldnt be some hardware thing I think.

I appreciate your effort and thank you for answering my question!!!

And sorry for my english! im not an english speaker...