Small bumps on the feet may be caused by allergies, as the feet may be exposed to a variety of allergens, such as textile materials in socks, and dyeing pigments, which can be the cause of small bumps on the feet. It may also be due to the presence of foot fungus, which is medically known as tinea pedis and is usually caused by a fungal infection. Different types of fungal infections may show up on the feet in different ways, such as running water, peeling skin, or the appearance of small bumps. In either case, it is advisable not to self-medicate, but to visit a regular hospital where a dermatologist can make a diagnosis and prescribe the appropriate treatment medication to achieve good results.