There was drama with my uv maps. They decided to "helpfully" maximise my uv space by stacking (basically symmetrical things neatly align themselves on top of one another to maximise efficient use of uv space...however because I'm painting the uv maps and there's different things on each side I absolutely do not under any circumstances want that) and I don't know when that happened or how to fix it.
And there were these random little black dots which I think are polygons (because they only show up in polygon selection mode) but are unselectable. I don't even know if they're actually polygons or glitches in the matrix as they seem to randomly appear and disappear.