Default My Android device is stucked on boot logo since I flashed the official stock rom

Hi,
I tried to flash to my Nexus 4, Google's official stock rom (KOT49H), by following this tutorial: http://www.android.gs/flash-android-...oogle-nexus-4/

It seemed like everything worked fine, and when the installation had finished my device got re-booted. Since then, my Nexus is stucked on the boot logo (over 15 minutes). I don't know what to do. Does anyone know how to fix it? Should I re-flash the stock ROM?

* My device is unlocked but I haven't rooted it.
Thanks!!