2/ I googled local locksmith emergency services, and called the first number I can find at 16:20.
"There will be someone at your place in 20-30 minutes!"
I called them again at 17:55 and asked them how long I would have to wait. "Oh, the locksmith canceled. Didn't you get a message? No, now it's too late and we can't send anyone else to you - you will have to call some other service." Assholes.
Then I looked up another service and called him, and _he_ showed up within 15 minutes. He charged €95 because this was after hours, which was reasonable, but I gave him a €5 tip and a good Google review because I was so pissed at the other service.
Today marks the official start of my vacation as I visit my father in Erlangen for two weeks (and I _definitely_ left my work notebook back at my apartment!). But when I took the bus to the train station, I saw in the train travel app that a train had an accident while moving around a station, and thus the route between Oldenburg and Bremen was blocked...
After some deliberations, I decided to take a route via Leer instead - going west instead of east. This will add more than three hours to my travels, but I am not in a hurry - and it's better than waiting around the train station for hours and then trying to squeeze into the first train into the direction of Bremen together with all the other passengers.
Let's see if this week throws any _further_ curveballs at me...