Default Unbelievable situation. please help

Hi everyone,

Today i tried to update my xperia j to the latest version 11.a.0.31 (4.1.2) OTA.
my device is not rooted and not unlocked bootloader, it's still on the factory status.

After downloading the update the device restarted, started the updating process, but then restarted and a blow arrow pointed to a device icon appeared and that's it, it keeps restarting without any thing launched there.

Moreover, the device can not be detected on my laptop (windows 7), i tried the SUS and it didn't work either (volume down + cable in)..

anyone can help please?