<specs>Intel x86_64, 1Tb ssd, 32Gb ddr3</specs>
<background info>
I shouldn't even have run of space. I got the warning on the lower right corner, but I thought it belonged to the guest vm I was using. I was not downloading anything, so I ignored it. It did not immediately occur to me that whonix virtual disk expands as needed, and even though I was not downloading anything, each browser tab I opened probably made the swap file bigger. The warning prompted again, now I had more space than in the last warning. Should be. Closed.
</background info>

Moments later I had a completely crippled system, and one day later after trying a few things, I am in the same position.
Every system setting seems erased. From the favs in the start menu to the wallpaper. All the configurations done during months, all gone. Even the monitor resolution has changed.
Arch can boot, but can't get out of a 0mb free space. Apps can't run. They can't write any file. The whole file system is read only. Firefox starts but gives errors and the only thing you can do is to close it. Everything freezes. Soon after boot you can't even click on the start menu so if you want to reboot, you have to long press the power button of the pc.
I have deleted over 60Gb of files, using Dolphin, using terminal, from arch-chroot, but still 0mb free space. df always reports 0mb free space. It also shows there is a gap between available space and used space, but even that does not seem to be changing.

I don't know what else to try. Is this even normal? To completely fuck up a system just because you unawarely go though a low disk space moment?
Any ideas much appreciated.