I have small blisters on my feet?

I have small blisters on the sole of my left foot. with some on the side (on an a calloused are I would consider the sole) They are not very sensitive to the touch. They have mostly clear fluids in them with occasional white puss. I do not have a fever or any of the other symptoms indicating foot and mouth disease and no history of any form of eczema of any form. It does not have the appearance of planter warts. any idea what it could be?