hello i have a pimple thing on the shaft of my penis, there is puss that comes out like a normal pimple only when i pop this pimple it goes away then comes back some times i get like 2-3 of them, there not sore just i cant seem to get a girl, i did go to the doctors and they said it was a blocked gland, but i have had this spot/spots for about 1 year and a half, please can someone help me out here thanks

oh and im 17 years of age, and yes i have had sex.