Power isn’t restoring after short circuit…

Hey folks,
I’m sure this is probably an ultra-rookie question, asked by none other than
…you guessed it… an Ultra-Rookie. As such, sorry in advance if I have trouble understanding any responses. Most of my limited knowledge of the electrical world has been acquired from watching YouTube DIY project videos, (which is an obvious craps-shoot) and sticking 2-prong forks, made of folded gum wrappers, into the electrical outlets of our high school gym as a teenager. I dunno which one has the worse odds for a good outcome, and that’s not really a coin I care to flip anyway… So I figured I’d try joining a forum instead.
I’ll try to include as many relevant details as I can.
Yesterday, I was doing some repairs on a guitar which required some soldering. I ran one of those little 10’, 1x male-to-3x female, ungrounded extension cords from a wall outlet behind me, and had the female end close to my feet. I hadn’t plugged my soldering iron in yet, but there was a USB phone charging adapter plugged ALMOST all the way into it at the time. I mean, there was the slightest little gap, which allowed you to see just a sliver of the 2 prongs. Right about the same exact width as the smallest size of guitar string… 010” to be exact. I know this because the string which I’d just removed from the guitar, fell off the table, and despite one-in-a-million odds, landed cleanly in that gap… That was a .009”.
Yup… Right from the frying pan to the fire.
Nothin’ but net…
Anyway, the string laid across both prongs, and there was an instant “pop”, which sounded kind of dull, or muffled. The power in both my little apt, as well as half of the apt next to mine is now out.
I live in a house that was sectioned off as separate apts, so there’s a few small breaker boxes scattered around the place. None of them are labeled at all, and one of the boxes isn’t a breaker box… It’s an old fuse box. (There’s a pair of Mains switches, and a small row of 20 amp fuses screwed in below them.) Luckily, I do know how to properly check/replace those as well as breaker switches. But unluckily, no switches were tripped, and all of the fuses were just fine. (No suit or burn marks, etc) There are burn marks on the USB adapter, and extension cable, but so far, that’s the only place I see anything like that. I toggled each of the switches I came across anyway, regardless of not appearing tripped, but no power has been restored. Oh, did I mention that my landlord JUST left on an out-of-country vacation?
The outage is across the whole circuit, and nothing that lost power has come back on since. My apt is a studio, and only has maybe 4 total outlets. I don’t have anything plugged in that makes big power demands, or an excessive amount of devices in use either. So as of right now, I think I found all the breaker/fuse boxes; all of which don’t appear to have been tripped or blown. On a scale of “1” to “goddamn impossible”, with the boxes being spread between different apts, and everyone having very different schedules, tracing each switch so it can be labeled is giving “herding cats” a serious run for its money.
So there’s my situation… If anybody has any ideas of what might be preventing the restoration of power to my apt… that don’t involve the ghost of my high school janitor, and/or the smug mention of “karma”, I’d certainly be very grateful for them. Thank you for your time.

P. S. I was just kidding about the ghost part. If you’ve got janitor jokes, by all means, fire away.