Welcome to Android Central! Does it respond to touch anywhere? It's possible the digitizer failed, in which case you'd have to contact Samsung for a repair (if still under warranty), or bring it to a local repair shop.
You could also try booting into Recovery and wiping the cache partition. Follow the steps in this video, but instead of selecting Wipe Data/Factory Reset, make sure you select Wipe Cache Partition. When complete, then select Reboot System Now.
https://www.youtube.com/watch?v=nA2eUek1H0I