i have had sex recently but i wore a condom always and this showed up at random maybe 2 weeks after. one day i woke up and it was there about 3 inches across it doesn't itch or anything just like my normal skin  but red. its right where my pubic hair grows the only thing that happened around the time it came up is i worked at an auto repair shop and spilled gas all down the front of my shirt and pants and had them on for around 30 mins untill i could get home but i have had them for around 2 months now and they havnt spread or itched or anything.