Shapes tool is creating lopsided objects: too wide on top & bottom, and thin on left & right

Hi.  I'm experiencing a strange issue with the Shapes tool on the Insert menu.  It has the default shapes such as a hollow square, lines, and other items.  It usually has created them where all sides were the same, but today it is doing things it's own way.  The top & bottom of each shape is always much thicker than the right & left sides, which are too thin.  Strangely, if I attempt to rotate the shape, it will preserve the thickness at a 45 degree angle, but a 90 degree angle still looks the same on all sides, as if rotate had no effect.

That's a picture of how my shapes look by default.  It is set to pen mode.

Thanks for any suggestions.