Black Screen after VM (VBox) crashing

Hey guys, I'll try to be as fast and rich in detail as possible
FIRST: I'm a complete noob in UNIX systems whatsoever.
SECOND: Had a Kali 2018 running on virtualbox like a charm. Worked 100% of the time. Couple of days ago I kicked the power plug off and downed the whole system. When I booted back up Kali turned all black after login, with only the cursor visible.
I googled back and forth, tinkered with commands a settings that I have no idea what they do or did and actually upgraded the OS to 2020 (biggest bummer so far); I managed to have the GUI show up a couple of times (and took a snapshot so I can manage by) but it just turns black when rebooted.
WHERE I'M AT NOW: I have a Kali 2020.3, black screen after login, no cursor or anything showing up, I can access TTY and just now I found out I'm able to login using an userI created a couple of weeks ago. This "working" user is not root nor does it have SUDO permission.
This machine is already configured the way I want and wish to keep it. I do not have the 2018 image used in VBox, which is sad.
So... anyone has ANY idea of what to do?