(I apologize ahead of time if this ends up on the wrong forum. Ever since the website was redone I have th hardest time finding /posting to garden advice)

i numerous pots of propagating succulents throughout my house. This pot in particular sits on my north facing window sill. I leave them be for the most part, stopping by to water and check in occasionally, as they've been growing well.

About a month ago, I noticed that the leaves looked not exactly withered but more so "pruney". I concluded that too much water was the issue (despite not watering them all that much).

when I checked on them today i noticed these strange bubble, blister like spots on the leaves. I've never seen anything like this in any of my succulents.

What's happening?!