I have a small red circle near my genitals in the upper part of the groin kind of like this: http://static-img-c.hgcdn.net/Media/_640x360/HG218_skin-wart-HPV-effects_FS.jpg, but less intense. It is just a round circle, with red color. It poped up yesterday, a day after i had sex with my girlfriend with a condom, i am worried that it may be an std, what should i do?