Ever since I symmetrized the mesh so that it was perfectly symmetrical, the armature started deforming whenever I rotated it.
This was a completely new armature I made from scratch, I can't tell if it's the armature or the mesh that's making this awful deformation. What is happening? I put the automatic weights setting.
Also, when I rotated the armature on its own, it stretches the bones. When I rotate just one bone it stretches only the tips of the fingers, and then mirrors the effect on the opposite side. How to fix this?