After a long uptempo run in racing flats that show forced me to do mostly on pavement, the ball of one of my feet started to hurt. The pain is located on the metatarsal bones on the other side of my big toe and second toe. It is mostly a dull ache like the area has been bruised, and it hurts only when I run. I can run through the pain, but I don't know if I should. I'd say it ranges between a 3-6 on a 1-10 pain scale when I am running, and it doesn't hurt at all when I am not. I have never had a stress fracture, so I don't know what one feels like. Can anyone help me to diagnose this?