What Causes Penis Itching With Pain After Intercourse?

hi...My problem is that I have so much itching inside my penis.1week befor I had a sex with my girlfreind,after that this itching problem start and sometime pain also.My girlfreind also experience the pain but for only one day.I think we used some veshline sourt of cream for mastrubation may be due to this.But is this possible that itching may be due to some cream.Plz help me doctor...