thanks11 is right on. Since you had them since you were 13 it is not a STD. You would have to see a Dr for proper diagnosis, but like I said thanks11 is right on with his/her answer.
It is most likely that the bumps all three of you are describing are sebaceous glands of hair follicles on the scrotum and lower penile shaft. They are normal and harmless. You'll most likely see hair growing from them (if not now, then soon!). And yes, hair can grow on the shaft of the penis, though most often just near the base.
Just my two cents but listen to the pros on here.