PSE distorts shape of circle after rotating

[#1]

I have a strange problem with rotating a layer, though I've rotated objects many times before without an issue.  The layer that I'm rotating appears below, first in its original fully circular form and second in the shape it takes AFTER I rotate it.  As you'll notice the second shape is no longer completely circular as the original shape was.

This distortion happens after rotating the image, whether I use a drop down menu and enter an amount for rotation or if I manually rotate the image.  I've tried rotating with the mouse, rotating while holding "ctrl," rotating while holding down "shift," etc. and the image always distorts when I rotate it. My question: Why can't I rotate the original image you see below without the image's circle shape becoming diestorted?

[#2]

At least according to the image you have posted, the original image does not appear to be a circle either. 

[#3]

The bar in the center causes a bit of an interesting optical illusion, doesn't it? At first glance it looks like a circle, but it really is an ellipse. I wonder if it was done on purpose.

[#4]

That's no optical illusion, Sir.  This is what one of those is supposed to look like.