Undo is a U turn backward, It indicates that you are attempting to return to a place you've already been. or UNDO a previous action.

So here is an interesting symbol for a Jeans button, and if you open the button model viewer… rotate it look at its face give it a spin… the colors are amazing in the viewer. Tried to simulate the florescent yellow/green and amazingly it did it in the 3D model viewer on this page. 

Hopefully you see what I mean and spinning that button so the face goes around in the direction the arrow point is hypnotizing…maybe it will undo some stress too..