What could a burn like sore on my labia be?

[Gdfml]

I know the first thing that comes to mind is herpes because that was my initial thought. I had unprotected sex with this guy a little over a month ago and everything was fine until about a week ago. I had extremely vigorous sex for quite awhile and when I woke the following morning I was extremely sore like a feeling of being rubbed raw. I had never completely shaved my pubic area and thought it was somehow part of the reason for having the the soreness. Now that incident was a week ago and I was still experiencing the sensitivity. I became curious and started looking at what was going on down there. 4 days ago it looked completely normal. Then just yesterday I spread my vaginal opening to get a better look and there was this burn like sore. It is red around it and pink in the middle. It isn't as sensitive as it once was but it is still tender. It appears as though it is reducing in size as the pain subsides. There are no clusters or pimple like blisters. From the pictures I have seen on STD websites they don't resemble what it is that I have. Other than the sore itself I haven't had any of the symptoms relating to herpes. The only thing is that my period is abnormal but I just got back on the pill so that may have something to do with it. I intend on seeing a gyn but in the mean time I would like some input.

[Gdfml]

Does herpes always appear as pimple like sores before it turns into the open blisters?  I have no crusting or scabbing and the tenderness has nearly resolved itself. I'm just extremely anxious to go to my appt at the clinic

[Vance2335]

Symptoms of a STD would not show the next day. My guess is that this is just irritation. But seeing a Dr is your best bet.