Hello and welcome to HCM. Thank you for your query. Sounds more like folliculitis to me, than ingrown hair. Although ingrown hair can occur at more than one site, it is unlikely. This sounds like folliculitis, even more due to the appearance of whiteheads. As you have recently shaved and although you are sexually active, the possibility of folliculitis is more likely than an STD. An STD can only be considered once treatment for folliculitis fails. Folliculitis occurs in areas which have been shaved or those which easily accumulate sweat or are constantly exposed to friction (from clothes, etc.). Treatment includes antibiotic coverage, warm compresses with a clean cloth 4-5 times a day for 15 minutes each time, taking a warm bath (immerse your body inside the water) for 15 minutes a day, you could also add epsom salt to your bath which would facilitate healing. Wear lose comfortable clothing, preferably cotton. You could also avoid wearing your undergarments till your healing is complete. I hope I have succeeded in providing the information you were looking for. Please feel free to write back to me for any further clarifications. I would gladly help you. Best wishes.