So I was using blender, when I accidentally clicked on Factory reset. I think I could've messed something up, because I'm sure after I did that that's when my problem first appeared: now I can't weight paint anything.
I've tried everything I could find online, but nothing works. None of the brushes in weight paint work, except gradient. If my mesh is parented to a bone, and I try to weight paint it, it simply moves it instead. If I try to paint either the faces or the vertices, it selects them instead. I tried reinstalling Blender, and turning on and off the weight paint options, none of them worked, it was still there.
Do you guys know how to solve this?