Foot discomfort

I was just reading about foot pain on Runners a World. Could this be it?

The adductor hallucis is a muscle that runs horizontally across the top of the foot, forming a V-shape with its center at the big toe. The abductor hallucis runs lengthwise on the medial inside of the foot along the arch. Pain in either of these two areas can feel like extensor tendonitis or plantar fasciitis pain. But, runners can clearly identify a tight and sore abductor hallucis from a plantar problem because the muscle isn't on the bottom of the foot but rather on the inside of the arch.

Problems with either of these two muscles can result from not having enough arch support in your shoes, but most typically if you have bunions. Expert sports massage therapist and Rolfer Allan Kupczack, who treats recreational runners and elite athletes like Kara Goucher, explains that a tug-of-war that can occur.

"When the adductor hallucis is tight and pulling your big toe towards the other toes, it eventually creates a bunion. The abductor hallucis becomes weak from being in a stretched position all the time, and often the origin of the abductor, down near the heel, is tender."

I would switch back to your other shoes and see about the pain. If it subsides you may have your answer. You could always back off the mileage a little and see. I would recommend some good stretching before and after your runs. I try to do this and then roll my feet often with frozen water bottles. This seems to keep my arches from yelling at me.