I blew up my backup computer

Although i usually use my laptop for most things, for the time being im without a modern phone and a computer (personal computer, my sis was kind enough to lend me hers) so ive been struggling to do much work or well, being online.
the thing is that i had this backup pc, im the kind of guy that likes having something to rely on in case something goes wrong.
so the computer is this small office computer, barely runs chrome, barely runs windows (its a miracle that the computer survived this long) and its the kind of pc that goes under a monitor.
So me in the desesperation of not being able to check my mail, i decided to plug it in and use it until i can get a new (or my old) laptop.

So i plug my mice, keyboard, monitor, wifi reciever and power and sit down on my desk...Hard drive failure.

"Huh, thats weird, this pc was working just fine last week"
i open the machine, move around some cables and try again. It works... Log in screen...
i try to type, and realize that my keyboard is not responding, which sometimes happens, just unplug and plug back in and works again. 

I lean into my computer to unplug the keyboard and somehow, my mouse got tangled with the power cord, and my stupid butter hands slips. 

Im not sure how this happened, but the cord made a shortcircuit, and the powersupply blew up on me, it was like flashbang went off right in front of my face, left me blind and my ears ringing.

so i end up in complete shock, smoke filling the room, and this gross plastic smell fills the room.i finally react and pull the cable out of the wall, then keyboard and open my computer once again to see what damage the pc took. the inside was full of smoke and smelled like death. 

Im not sure if the motherboard survived or if anything else still works, but im no technician and im scared to plug it back in. probably it was time to get rid of the old black box one and for all