Google images is having problems working. There is something wrong with their urls. I don't know what causes it but they suddenly became very long and stopped working.
I think it's because Google Photos became separated from G+ with the most recent update. Now, I think the pictures have to be shared, at least privately, for them to display. It might also have to do with machine/browser because certain people see the images while others don't. The URLs specify whether or not the image is shared, which is why some are super long (unshared) or relatively short (shared).
I'm not certain of any of this, but it's my working theory.