I saw your new thread with Dr. Hook. It was unnecessary, but now you have 2 opinions. He not only agrees with my original reply, but I agree with his. We will be happy to comment further if you get more information from your daughter's doctor, especially when the herpes test results are available; there is no cost to add a comment using the green "Post Comment" button. Please pick one thread or the other, however. Dr. Hook and I will both look at it.
Is it "possible" to catch genital herpes without some sort of sexual contact? Maybe. But if so, it is very rare; for practical purposes, all cases are acquired sexually. Sex in this context includes oral-genital contact, which can transmit HSV-1, the normal cause of oral herpes, to the genitals. But herpes is not caught from toilet seats, moist towels, shared clothing, and that sort of thing. In past years, such explanations were thought to explain some cases, but if they really occur, they are extremely rare.
That said, the symptoms you describe (not counting the past oral sores, which might have been canker sores) certainly sound suspicious for an initial genital herpes infection. All in all, herpes is the most common cause of this sort of illness, but of course not in people who could not have caught herpes to start with. And yes, there are several other medical conditions that could be responsible. "Something viral" other than herpes is one possibility. A condition called Stevens Johnson syndrome also could go along with sores in the mouth (usually also with a generalized skin rash). If she (and you or her father, assuming you are her parent) come from a Mediterranean background, such as Turkish, Armenian, and others, there are genetic conditions that can cause this sort of thing.
Swab tests from the sores look for herpes simplex virus itself; blood tests look for antibodies, the immune system's response to the virus. I suggest you wait for those results. If they are negative, the doctor might request another blood test in a few weeks, since it takes time for antibodies to develop.
If your daughter's sexual history is accurate, you can expect these all to be negative. But surely you understand that in today's world, many 15 year old girls are in fact sexually active but might not be forthright about it with their parents. If the gyn is experienced in recognizing herpes and considers that a good possibility, then your daughter should be treated with anti-herpes drugs, without waiting for the test results. If she has herpes, treatment will greatly speed healing and rapidly reduce the pain -- and a rapid response to treatment also would tend to support herpes as the cause.
Assuming her history is accruate and she doesn't have herpes, ask for referral to a dermatologist as the next step. That's the specialty most familiar with all the other things I mentioned, plus others, that might be responsible.
Bottom line: Whether or not herpes explains this problem depends very strongly on whether or not her sexual history is accurate. If it is, then almost certainly this is something other than herpes. I do hope you and her father will be understanding and sensitive, and not condemning or accusatory, if it turns out to be sexually acquired herpes. While I am definitely not a fan of the Republican VP candidate, Gov. Palin's reported response to her teen daughter's pregnancy is a good model.
I hope this helps. Best wishes-- HHH, MD