No, anxiety doesn't wreak havoc on your pelvic region, and you're really not describing your pelvis. Anxiety does different things to different people, and when you have pain, anxiety makes some people focus on that pain so much it seems like it hurts more than it would normally, when you would ignore these little aches and pains and they would go away. Given you're afraid you have an STD even though apparently you don't have one it would make sense you would feel some pain in the vaginal area. But think of it this way, when you're afraid you have an STD because of activity that can cause one, a person without anxiety does something about it and that's the end of it. An anxious person worries and worries. It's the anxiety you need to attend to, it appears. Ever been in therapy? Also, stress doesn't come from being exposed to an STD, it comes from the way we think. Life is always stressful if you think about it enough; most people don't do that.
I imagine you have done too much reading because the more you Google the more afraid it will make you.You were worried about herpes a few days ago despite no symptoms, now you added pelvic pain (which might be a real pain or might be just imagined from fear). Perhaps you should talk to your doctor about this and/or ask her to refer you to a therapist to deal with your health anxiety.