I have a small red sore on the bottom of my left foot...?

i have this small red sore on the sole of my left foot. i dont think its from irritation as it seemed to appear almost overnight. Could it be a verruca? feels a bit sore when i walk. not sure what a verruca looks like. Help please?
Answer:
it may be just a blister, i get them a lot from running. if it is only one red spot, then it could be possible it is a blister, you should probaly wait to get it checked. if it gets any bigger than it is already, it could be a wart or something. and if you touch it make sure you wash your hands so as not to spread it to the rest of your body.

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