iMac 5K 2019 startup and then black screen
My iMac 5K 2019 (I believe) just randomly began to give me a problem. I used it two days ago, and shut it down, and then I tried turning it on today, but after the apple logo showed up and the progress bar began moving further to the right, the brightness of the black screen goes up a tad bit and then it stopped moving around the halfway point and then after a few seconds, a flicker happens where I can see the mouse cursor up in the top left corner of the screen while having a black screen, and then it goes away and I'm left with a black screen.
I hear that the fan is running, and sadly I had my mute button on before, so I can't tell if the startup sound plays or not, but I imagine that it does.
What the heck is going on? Anyone know of a fix?
I also let it run, and it eventually got darker, as if it was beginning to enter display sleep mode, and when I pressed a key on my keyboard, it lit up again, but still a black screen.
iMac 27" 5K, macOS 10.13