Many penis lumps are harmless and don't need treatment. Fordyce spots are small yellowish or white spots on the head or shaft of the penis. A painful blister or sore on your penis could be caused by herpes, which is an STI caused by the .
A lump on the penis is not typically something to worry about. However, if it could also be a symptom of a sexually transmitted disease or forms on the shaft of the penis and causes a noticeable hard lump or band of tissue.
A lump or scar tissue (plaque) forms on the lining of the erectile tissue which men often describe hearing a loud 'crack' with pain and bruising of the penis.