[Q] Secure boot error topic

Last night I had a secure boot error after I tried flashing a custom kernel over a new ROM* I also just flashed.

The ROM came pre-rooted so I downloaded freegee and tried to unlock it, but no "unlock" option; all it showed was "re-lock (restore efs)". So i assumed it was safe to flash and viola! Secure Boot Error!

I wrestled with it for about an hour, looking for a way to revive my OG without losing all my data, and I had the problem of a faulty power button. I tried VUp+VDown+Power which only turned off my device, I tried VDown+Power which put me in hard reset mode, then something interesting happened. I tried VUp+Power which after a few seconds my OG's screen flashed twich and the error message now read:

Secure Boot Error
Cause: Device unLock!! so Boot successful!

from:

Secure Boot Error
Cause: boot certification verify

The new message only shows when I reboot into recovery though, when I turn off my phone then turn on or reboot, it boots like normal.

Anyone have any idea what this is, what it means or if it means my bootloader is unlocked or not?

Decided to post it here in General since I thought this is a matter of general interest and I'm not asking for help/troubleshooting, just asking a simple question.