Any lump, especially if it is new, should be examined by your podiatrist for a diagnosis. There are many possible reasons for a lump (including an abscess), some of which are serious and some of which are not. An abscess is usually serious, and often requires antibiotics.
Foot odor, also called bromhydrosis, can be caused by excessive sweating, fungus, infection or a combination of the above. For sweaty fee, soaking them in brewed, cooled tea for 20-30 minutes twice a day can be very helpful. Avoiding cotton socks and instead choosing wicking fabrics such as acrylic blends will help keep feet drier. Alternating shoes daily is helpful to allow them to dry out between uses.
If you suspect a fungal infection (scaling, cracked skin) or a bacterial infection (red, swollen, warm skin) you should be seen by a podiatrist for evaluation and treatment.