Hi
Looking at your 2 pics, reminded me when using my old Nikon F2 film camera that the depth of field (sharp zone) on a lens specially when focusing close to the camera was showing on the lens barrel always a farther distance (in focus zone) in the back of the focusing point compared to the front distance. This is what seems to happen on your 2 pics. It is specially more visible on the pic where you have ants. On this pic the pavement (ciment) is perfectly in focus at the focus point and farther away from it that in front of that point where it is out of focus.