i'm seventeen years old and i've had this penis rash below the head just above the shaft (i am circumcised) for about 5 months now, it is only on the middle and somewhat the right side. it appeared after receiving lots of oral sex from my girlfriend in october. she was not being very gentle and i figured it was just irritation. for about 3 months it was typically dry and itchy when i would wake up in the morning, not itchy to the point where i had to scratch at it. my girlfriend was a virgin and we only had sex a few times, and we used protection (with spermicide lubricant). she even got tested for STD's and everything came back negative, although she did have an abnormal pap smear. i have not had with anyone else before, or anyone after this.
since october i have been applying various lotions and things like vaseline, baby oil, cortizone-10, etc. all of which has reduced the redness and gotten rid of most of the dryness. it stopped itching/being irritated back in december but the redness has stayed. and if i masturbate it gets worse and i have to start the process all over again.
i haven't seen a doctor about it yet because i have noticed any sores, discharge, pain, etc. and i would also have to tell one of my parents what my problem is and it would be horribly embarrassing .
does anyone have any idea what this could be? i'm wondering if it's just irritation/dryness (it's still winter here) or something more serious like an STD such as HPV or something.