I kinda need to get better about backing things up again. I had that same issue with my laptop as several months ago. (Bit of a hassle finding the post where I mentioned how I resolved it. First, I thought I'd look through the old Daily Writing Topic posts, but realized that was a bother (although it actually would've made things not terribly hard if I just checked my first and last posts). However, I realized I could use my progress spreadsheet to find it... and, while looking over that (which the saved copy on one thumbdrive stopped midway into LL1 for some reason), I finally remembered that the issue previously happened while drafting Pointy Hat, which narrowed it down... only to realize I didn't explain things in the Daily Writing Topic, but I had a day so I checked the previous What's On Your Mind topic and found it. (Although, admittedly, the solution seemed more like luck than anything -- after leaving it on for a while (after turning it off repeatedly), I pressed the power button off then on and it worked... which kinda seemed to work this time, too.))
Of course, there's no particularly great way to back up my editing, save either using One Drive or something like Drop Box (since the files get kinda large to email myself). However, I'm thinking I can probably just use a thumbdrive to back up the last few recent copies and, as I go along, get rid some of the back-ups on the thumb drive.
And, despite it being just a day-and-a-half's interruption, I have a lot of catch-up work on my hands since I was noting changes in Google Docs that I need to migrate to the normal document. I'd rather foolishly thought things wouldn't be a big deal since I'm just doing the quick-read (and spot-fixes) on HPCS, but I kept noticing things I really ought to fix just in case I missed them on the editing runs.
(On top of that, when I was checking one of my thumb drive back-ups, I realized that I didn't have a copy of STMHB on it. Kinda gets hard to keep track of all this.)