I didn't recognize your username until I posted my reply. You're the same person who was inappropriately concerned about hepatitis B. Most likely your own provider reassured you about herpes as well. Note forum rule about number of questions per user. You may not post another question for 6 months.
None of the symptoms you described in your other thread or this one has anything at all to do with your oral sex event. It is likely you would benefit from professional advice about an apparent emotional overreaction to that event. I suggest it out of compassion, not criticism.
No follow-up comments or discussion, please.
Relax. There is no chance your buttock lesiosn were due to herpes.
It is true that genital herpes can affect the buttocks. But not the initial infection. Genital herpes virtually always is acquired on the genitals or the anal area (penis, anus, vulva in women). The virus then migrates and persists in sacral nerves, i.e. that group of spinal nerves that come from the lower end of spinal cord. Recurrent herpes can then happen pretty much anywhere served by the sacral nerves, which includes the buttocks. Most recurrent outbreaks involve the genitals themselves, but recurrences can involve anywhere in the "boxer shorts" coverage area. Every recurrence is localized in area (typically just a few lesions in a small cluster), usually occurs in more or less the same spot within 1-2 inches, and always occurs only on one side of the body or the other (or the body's midline, but not across the midline).
Also, for practical purposes you cannot catch HSV-2 from oral sex, only HSV-1. If exceptions exist, they are extremely rare; I have never seen a case. Therefore, your HSV-2 test result is irrelevant: if you had acquired herpes from receiving oral sex, it would be HSV-1, not HSV-2.
The numbers HSV-1 and -2 refer to different versions of the virus. They do not refer to where the infection occurs. Genital herpes is usually due to HSV-2 and oral herpes almost always HSV-1. "HSV-2" does not mean genital herpes. There is no blood test that can tell where on the body someone is infected. (You might understand this already, but from your question, I wasn't sure.)
1) Your itchy red spots were something other than herpes. I cannot guess the cause, but if the spots looked like pimples, that's probably what they were.
2) No. Since you have had cold sores, probably you are immune (or at least highly resistant) to catching HSV-1 again, anywhere on your body.
3) It takes up to 16 weeks to reliably develop antibodies to HSV-2. But for the reasons I already mentioned, HSV-2 is irrelevant to this situation. Your negative test shows that as of 4 months before the test, you had not been infected with HSV-2. If a provider decided to test you for HSV-2, it's obvious s/he isn't especially knowledgeable about genital herpes; and if you requested that test yourself, you jumped the gun and wasted your money. Perhaps you will find it reassuring that you have not been infected with HSV-2, but that's obvious from your story, without the blood test.
Good luck-- HHH, MD