"Could not move selection because selected area is empty"
I am trying to make a photo collage. The instructions (on YouTube video) say to create a circle, then fill it with a foreground color (on its own layer). Then keep the circle selected, add a new layer, right click on it and select Stroke. Every time I right click on it to do the Stroke thing, it says "could not move selection because selected area is empty." I tried googling this and came up with a number of different answers.
Can anyone please tell me why this isn't working for me? I have deselected and selected, deleted the new layer and tried to create a new one, and so on.
Here is a screenshot. I'm working with the purple ellipsis in the center.
