There are many things that can cause penile bumps, some of which are benign and others that require treatment. So I recommend that you speak with your doctor
. Molluscum contagiosum is a viral infection that can cause small dome-shaped bumps that are painless; this is a sexually transmitted infection but is not serious, and a physician can often remove the lumps without further recurrence. Genital warts
can manifest as penile bumps though often with a pebbled surface. Follicular cysts are dome-shaped nodules that can appear on the penis though more typically on the scrotum. These are benign lesions caused by the accumulation of fluid in the glands or hair follicles of the skin. Swollen glands can also cause a condition called Fordyce spots and Tyson spots. There is also a condition called pearly penile papules that arises near the glans of the penis that are benign and symptomatic. Scabies and syphilis can also cause penile bumps and do require treatment. Lesions that arise from under the skin (you can move the skin over the lesion) can represent something more serious. Skin cancers are less likely to present the way you describe, but are important to rule out. The best way to tell whether these lesions require treatment or are just normal variants is to go see your doctor. It can be uncomfortable to see a physician for this kind of question, but physicians deal with these questions very commonly, and it is important for someone to take a look and determine whether further diagnosis or treatment is necessary.