Well, I think I've figured out what happened. I went back and looked at my calendar, and realized that, because of an unusually massive amount of stress, I actually cannot really remember anything from about five days of the last week or so. So, what my mind is registering as less than a week, has in fact been almost two. (I also missed an online paper submission deadline. Whoops.)
Additionally, the riccia that i had in his tank has been... not doing well. I scooped that our this morning when it occurred to me that it might be a contributing factor.
I literally feel so horrible I spent five minutes verbally apologizing to Pearlicus as I fussed over my chemical bottles and test strips. I think my roommate thinks I'm mentally disturbed right now.
When it became evident that daily water-changes were going to be needed, I prepared almost six gallons of water, which is sitting in buckets in the powder room right now, so when I get off work, I've decided on doing a complete, 100% water change. I'll rinse the gravel, take the swords (which haven't actually rooted yet) out and replace them with a Bolbitis heteroclita and some anacharis I have, and I'll keep the marimo ball in there as well.
The stress of what will basically be a new tank would be gotten over more quickly than the stress of almost a week of ammonia exposure, right?
I feel so terrible about all of this. Pearlicus must be at least as miserable as I've been for a week now, and I have no idea how to make it up to him.