Shape tool not creating new layer

Hello,

I can't seem to figure out how to make Photoshop CC create a new layer whenever I draw on top of a previous shape. So if I draw a shape it does create a new layer. But if I want to alter that shape with another shape it adds to the original shape..it does not create a new layer.

I just learned more about this. If I draw a shape regularly it does add a new layer. But in the video below I am holding shift to get a circle and it does not create a new layer when I do that. Is this normal? I just double checked and I'm not making this up.

I can do it manually but I don't always remember and that's a hassle. I created a 10 second video showing what I am talking about it that helps.

See here ==> Click for screencast

Any help would be appreciated.

If it helps I am using Mac OS Sierra