weird skin coloured bumps on base of penis?

Hi, I'm 17 and, clearly from the title, male. I have recently noticed that I have skin coloured bumps at the base of my penis which are about 0.5 - 1mm in diameter. They dont cause me any pain or discomfort, but I have noticed that since about six months ago when I discovered them, they are slowly spreading. I'm currently in a long term relationship, about a year, and my girlfriend has been tested for STIs and STDs with negative results. I have only had sex with two other people, each with the same results as her. I have conaidered genital warts but they dont appear to be spreadong fast enough, they dont seem big enough and my girlfriend does not have a single one on any part of her body -we have frequent intercourse and still do, regardless of the spots/bump things. So, my question is this A) what are they? B)Should I be concerned? C) What do I do about them? - can I get rid of them? And finally D) do I need to go to a GUM clinic or doctor? Baring in mind I've never been tested for anything. Please help me out on this, I'm really concerned and reasonably worried about my well being. Thanks.