Unhappy [HELP] Touch sensor doesn't not respond

I've bought Xperia SL almost a years ago. But now i'm having serious problem. Theres no reaction when i tap the screen/ backlight button. only power, shutter key and volume keys working. It hapenned just now, few hours ago my phone still normal. Help me please... what should i do?

note : in CWM menu can't press back button on screen also