This could be plantar fasciitis, a bone
spur, a plantars wart, or something
else.

An irritation of the foot can create
problems in the ankle, then knee, then hip,
and then the spine. Those problems
develop from compensating gait to
avoid the foot pain.

First, I might consider getting shoes
that provide good support, especially
in the arches, and maybe the ankles.
Look at the bottoms of your shoes, and
see where they are wearing, and if
there is any difference between the
wear patterns on your left and right
shoes.

If this problem persists, see a physician.