As far as I know, the "good" ending is really just the one that didn't go horribly wrong, which depended on a choice earlier on in Mikko's route. You're good, it's just this day ended like that.
No, I just got this game for the first time on 0.15 like 3 days ago. If it helps, I remember I was in the middle of playing on that file and the game crashed, and the buzzer thing started happening when I got back on.
Whenever I try to get on my main save a buzzer sound plays and doesn't let me. My last backup save was 3 hours before the main one. All the other save files are working fine, it's just this one, which happens to be the one I progressed the most.