I used to get some crazy right heel pain last year when I was playing competitive football (soccer). This was because I was running almost 10km in boots. The grounds were hard as well.
Is it really sore particularly in the mornings?
If so, it is probably plantar fascitis. Hurts in the heel but it is actually a lack of arch support. Look into orthotics or strapping the arch (which is what I do).
I also started working out my tibialis interior (the muscle that runs along the shin). This is because my calves were taking too much of the strain, pulling the ligaments under my arch, hence the heel pain.
