Dark room for calibration is useful, but IMMEDIATELY after the calibration is finished you must turn the lights back up to full brightness (or open the blinds, or whatever) so that you can compare the screen to prints in proper bright lighting.
Calibrating your screen at night time is fine, as long as the artificial light in your room is as bright as daylight. There should be no (well, negligible) difference in the light around your computer 24/7.
Yeah, see how it goes.
I'm always so regretful to say this, but there might be a problem with the calibrator.
Is there another computer in the house that you can try calibrating, to see if it also gives you a weirdly low brightness result?
I'm old-school. My off-site backup is literally disks kept at my friend's house (and I keep his disks at my house).
Some more info in the second half of this article: https://www.damiensymonds.net/how-do-i-retrieve-lost-or-damaged-images/
Some of these are very mild. So let's see if we can get away with the easiest method of all. That is, add a Solid Color layer of good skin colour, and set its blend mode to "Color". Then invert the mask to hide it, then use a 10% white brush to paint it over the blue areas.