Hi Hippasus, yeah I've heard of this happening once before, last year, but can't actually repeat it. (The one case I have on record actually happened in the Scrapyard, even...) There must be something really weird about the conditions, because people self-destruct there fairly frequently and it doesn't normally occur. Pretty sure this started becoming a (rare) thing due to the scoresheet overhaul for Beta 9.
I need more data in order to solve something like this, like a save file would be ideal, in case there's something involved there, but of course unless you made a backup manually, you likely won't have a save from before you self-destructed since run data is removed at that point. (The only way you'd have a save is if you had stopped the run on an earlier day, since your save would be backed up as part of the daily backups, but that's a rare and unlikely coincidence for an early-game run...)
Interestingly we don't even have scoresheets for runs below-9, so we can't even investigate that for details xD (that's done to keep all those scoresheets from polluting the data for "real" runs that get off the ground)
Wish I knew how to repeat it, since this is the second time now. Guess I'll try again and see...