What Causes Pimples On Penis With Shivering And Fatigue?

Hi doctor, i'm 21, i work for a bpo and work at nights, from 10 in the night to morning 10, which i joined recently(2 months back). i had hiv tests done and got 0.04 non reactive results, the main reason i had this test done is because i was feeling weak. my hands shiver a lot. i dont know is it because of me not having proper food at right time or other reasons, i had sexual inter course as in completely with two girls, and with three other girls i might have let my pennis enter into them may be once or twice like one or two seconds, recently a pimple kind of thing started popping up on my pennis, its not kind of boil, nothing comes out of it, and i researched about herpes and guess its not even that, its exactly where the pennis starts. its not on the pennis but on the skin, now it has become two, one above the other, i suppose it might have started coming because of two reasons, 1. hygiene 2. sex, so dont know wat to do about it, please give me any advise