Look, I had sex and my stepmother dosen't know about it but she's taking me to get some birth control sometime here soon. I know that I can send her out to talk to my gyno personally but then she will know something is up. Will my gyno say anything and will it affect my exam if I lie and say that I am still a virgin?
Just tell her that it's an embarrassing situation for you and you'd rather see the doc on your own. In any case, your gyn is NOT going to discuss your virginity or lack of it with you because it's none of his business. Nobody is going to ask you. Relax and breathe. Doctors NEVER ask that question because, like I said, it has absolutely nothing to do with them.
I'm not familiar with guidelines for STD testing but HPV testing isn't generally recommended for women under the age of 30 due to the ability of the immune system to suppress these infections. Too much screening can lead to overtreatment which can be harmful not to mention the costs. Also, not all HPV types are high-risk for cervical cancer. Types 16 and 18 are the highest risk - http://www.thehpvtest.com/about-hpv/high-and-low-risk-hpv-types/
http://www.cancer.gov/cancertopics/factsheet/detection/Pap-HPV-testing "The guidelines advise that routine Pap and HPV cotesting be limited to women age 30 and older because transient HPV infections are very common among women in their twenties. Including routine HPV testing in cervical screening of younger women would detect many infections that will be suppressed by the immune system and not lead to cancer."
To add to this - STD testing is not routine. In most places you have to specifically ask for it. Plus you have the fact that gynecologists are now recommending pap smears from age 21 ... I doubt the poster is 21. So, all in all, I really don't think the poster need worry about being asked whether she's a virgin or not.