This is probably caused by you forcing your system to shut down. The key thing here is to boot back into OS X, take a look in Applications/Utilities/console to see if there is a log report, cause of preventing shutdown at the time of the switch off. You can safely remove any USB peripherals, disconnect connected Optical drives to see if its hardware preventing shutdown in the OS X environment.
I don't understand much about it, but I don't see anything out of ordinary.
25/04/2016 15:26:46.655 shutdown[421]: reboot by Bulat:
25/04/2016 15:26:46.000 kernel[0]: Kext loading now disabled.
25/04/2016 15:26:46.000 kernel[0]: Kext unloading now disabled.
25/04/2016 15:26:46.000 kernel[0]: Kext autounloading now disabled.
25/04/2016 15:26:46.000 kernel[0]: Kernel requests now disabled.
25/04/2016 15:26:46.655 shutdown[421]: SHUTDOWN_TIME: 1461580006 654624
25/04/2016 15:26:46.000 kernel[0]: Process launchd [1] disabling system-wide I/O Throttling
25/04/2016 15:26:46.000 kernel[0]: Process launchd [1] disabling system-wide CPU Throttling
25/04/2016 15:26:46.655 com.apple.xpc.launchd[1]: (com.apple.xpc.launchd.domain.system) System shutdown initiated by: shutdown.421<-sessionlogoutd.420<-launchd.1
25/04/2016 15:26:46.657 com.apple.SecurityServer[73]: Killing auth hosts
25/04/2016 15:26:46.657 com.apple.SecurityServer[73]: Killing auth hosts
25/04/2016 15:26:46.657 com.apple.SecurityServer[73]: Killing auth hosts
25/04/2016 15:26:46.657 com.apple.SecurityServer[73]: Killing auth hosts