I've decided to call this shutdown because that's what pretty much happened. I was browsing on /x/, on 4chan, to see if there was anything that would creep me out. I was halfway through a thread and suddenly my screen went black, illuminated only by a small white light in the middle. The mouse was still there, I have it edited to be a crimson elephant - But now, it was the standard white pointer. I moved my mouse around a little and I could move it. I moved it over the white light and saw that the pointer shifted to a hand - I could click it. I clicked this and the entire screen faded to pure black, the white light fading.
The only light on was a green light from my keyboard, for the right number pad's number lock. I held the my hand over where all of the heat radiates from my fan and it truly felt like ice. The room was cold already, but this truly felt like I was holding a block of ice, temperature-wise, of course. I turned off my computer via the power button, then started it again after a few seconds. When I turned on my computer, I went through a start-up sequence, as I usually did, but when I got to the log in screen, it started to get weird. I normally have a light blue background, but now it was blood red. I simply thought it was a hack of some kind that had somehow corrupted the main screen. I typed my password and logged in successfully.
The screen was still red, but my internet connection was cut. I checked my wireless, my router, and my available connections. All were fine. I re-established a connection with my router, but it immediately shut me off. The lights on my router suddenly shut off, almost as if it had just been unplugged. I looked at it, then looked to my side. The plug was there and on. I didn't know what to make of it, but I had some games that did not require internet, so I was fine. I decided to finally study the screen, and noticed that all of my files were missing from the desktop page. I pressed the windows button on my keyboard and saw that everything was missing, except for Google Chrome.
I clicked it, and, despite that I was on Mozilla Firefox before, it asked me if I wanted to restore my browsing session. I shrugged, and clicked it, wondering what would be there - But what I saw disturbed me. It was nothing but a gif, covering the screen. It was a little girl waddling, with blood patterned on her hair. She looked up and stared at me. I stared back, immediately noticing black voids for eye sockets. I quickly put my finger down on the power button and shut it down, then started it up... And everything was normal. Sadly, I did not think of pressing 'Print Screen'. Not like anything would've happened if I had, having rebooted it. I don't know what happened, but I'm scared. I just thought that if I shared this story, maybe someone else out there could have had the same experience as me... Maybe I could show them they're not the only person to have had this happen.