In mid September I noticed that the side/back of my left heel (outside of hamstring) had a burning pain upon flexion of the foot. I work from home so was able to change to open backed slippers and only put on full shoes when I need to go out. I thought it was just bruised from wearing a relatively new pair of shoes. The pain is still there when I flex the foot (cannot do hamstring stretches or downward dog in yoga), so just rest is not helping.