Default Cm11 Nightly 20140307 issue

Hi, i was on Cm11 20140306 (i'm followed ota of cm11 from january) and all works perfectly, i use elementalx kernel from about 1 month, this morning i've updated to cm11 20140307 with cm stock kernel, after about 15/20 minutes when i've tried to wake the phone the screen stay black, if long press power button nothing happened (I was very very scared), i long press again power button and the phone power on with google logo etc, this happened 2 times, after i've tried to flash elementalx and it would seem ok, but what's wrong with last update of cm11 and its kernel?
Greetings