I have a small bump on my left foot under looks like a pimple and hurts?

Fibroma: A small pimple like lesion that appears on the foot may be a fibroma. Fibroma are small fibrous tissues that appear either superficial to the skin or they may appear subdermal. Many times they are painful to touch. See a Podiatrist or a Dermatologist to rule out other possibilities. Skin cancers can appear innocuous and must be checked out