Black screen with movable flashing mouse after OS loading screen

Computer was fine, then today, out of no where, I turned it on and immediately after the Gigabyte loading screen, when it usually goes to the windows 10 lock screen, it just stayed black. The mouse appears, and I can move it around. It keeps flashing between a blue ring and the mouse with blue ring beside it. Shortcuts like ctl shift esc, and ctl alt delete dont do anything.

I tried letting it sit for a few minutes and now the mouse is just normal white but screen still black, and no keys do anything. I was recently having a memory problem, and I turned off some things like NDU and NULL. Not exactly sure what they were but people said they might help with the problem and they did, but could they be the cause of this problem?

Also, sometimes, when the mouse is flashing, the screen also flashes between white and black really fast.

Any help is appreciated.

In case anyone ever gets this same issue. It went away after a day. No idea why.