Default [Q] GT-I9505 doesn't reboot after flashing kernel

Hi,

I've flashed a kernel for multi boot. It says it was successfully.
After I hit reboot, my SGS 4 turned off. When I try to boot, it stocks at the Samsung logo.
I can't even go to recovery or download mode.

'Kernel is not seandroid enforcing'

I got a Nandroid back-up on the external SD and on my PC.
Is there a way to go to recovery or download mode?
Then I can install STOCK or restore the back-up.