Q: screen is not working

Have you tried holding home+power button until the apple logo appears, in order to reset your phone? Is you iphone charged? Have you triend connecting your phone to itunes, does itunes recognize it? If phone works, and you can recieve calls,activate siri,etc, then there's a possibility that your lcd is broken. Take your phone to an apple store, and have them fix it for you. Hope I helped

Donnie.

Good tip, it worked !!!

Thank you, thank you, thank you.  Holding Home+Power until apple logo appeared cleared my blinking & frozen screen!