Welcome to the STD forum.
I reviewed your discussion with Terri on the herpes forum. I agree with her judgment and advice: even before the current test results, herpes was a very unlikely explanation for your symptoms. I would also add that the nature of your exposure -- described on the herpes forum but not here -- was one of low risk for herpes, since it was only a single exposure. With an HSV-2 infected partner, the per-exposure transmission risk probably is in the range of 1 in several hundred to a couple thousand. And as Terri said, your peri-anal symptoms didn't suggest herpes, both because of the location (as she told you) and the description of them. And you had an obvious alternative explanation, i.e. the antibiotics that may have triggered a yeast infection.
The additional data provided here further support the conclusion you didn't catch HSV-2. You have been quite over-tested; most likely you are doing it on your own (e.g. through an online lab?). The IgM testing in particular was a waste. Despite the standard advice that it is supposed to detect infection earlier than IgG antibody, it actually doesn't do so. And it gives lots of false positive results -- even if one of thsoe results had been positive, it would have been confusing and upsetting, without helping determine whether you actually were infected. FYI, here is a thread that discussed HSV IgM testing in detail; it's 4 years old but still accuarate:
http://www.medhelp.org/posts/STDs/Confusiion-over-other-IgM-Herpes-posts/show/248394
However, the HSV-2 IgG result is reassuring. Around 70-80% of new HSV-2 infections would produce positive results by 5 weeks (34 days).
From a purely medical standpoint, I see no need for any additional testing. In my opinion, you can be completely certain you didn't catch herpes and that you had some other cause of your peri-anal rash/irritation, likely a yeast infection related to antibiotic treatment. (Did you seek professional attention and diagnosis? If your symptoms are continuing, you still should do that.) However, if you remain concerned about herpes, i.e. if you need the additional reassurance of a definitive blood test result, go ahead with your plan for a final IgG HSV-2 antibody test 3-4 months after the exposure. For sure stop wasting money on IgM tests.
I hope this helps. Best wishes-- HHH, MD