I broke down today, and got an X-ray and doctor’s opinion. She thinks that the most likely diagnosis is plantar fasciitis, though it could also be a bruise.
From WebMD: Plantar fasciitis (say “PLAN-ter fash-ee-EYE-tus”) is the most common cause of heel pain. The plantar fascia is the flat band of tissue (ligament) that connects your heel bone to your toes. It supports the arch of your foot. If you strain your plantar fascia, it gets weak, swollen, and irritated (inflamed). Then your heel or the bottom of your foot hurts when you stand or walk.
I HAVE had charlie horses in my arches; but this pain had an obvious cause. Anyway, I am not pain free, but will get back on the AT rather than go stir crazy!