Restarting, Splash screen, Black Screen with login, no access


After installing kdf5 Disk Space utility, having done some adjustments in network serving restarted the system.
Sudenly after usual green splash screen with some boot option a black screen appears with:

Welcome to OpenSUSE Leap 42.1 - Kernel 4.1.27-27-default (ttyl)

Hint: Num lock off

linux-flw3 login:_ (blinking cursor)

My admin password is not beige accepted here. Simply cannot get acces any further.

I have newer used any password to log in in that stage. The system has always opened smoothly and then on KDE Plasma desktop there has been a prompt for admin password.

I have tried to restart the computer all in vain. The same logon prompt.

I will appreciate any prompt and helpful solution if any.
Thank you in advance,

OpenSuse Leap 41.2/KDE Plasma 5.2(?)

After some tries I have discovered that if I insert my user and password I am probably taken to my home place:

ac@linux-flw3:~> _

At least there are some chance to use some magic commands.
But which, to get into?

This means that ( at least ) one of your adjustments causes a failure in starting the X server, which is needed to run a graphical desktop. What you see now is the console.