Your symptoms sound like bacterial folliculitis to me. And it think the timing suggests this as well, with your shaving. Can you look and see if there are hairs coming out of the bumps? IgM testing is NOT recommended to diagnose genital herpes. There are many many false positives on this test and it really gets confusing for patients. Your IgG test for HSV 2 is solidly negative Since your most recent partner is HSV 2 negative and you’ve not had sex with anyone else for 8-9 months, it does not make sense that you have HSV 2 infection. You were wise to check this out further.
The screening test that you had done is not as sensitive for HSV 1 as it is for HSV 2. It misses about 1-2 out 10 cases, so it is possible that you have HSV 1 infection, despite the results of the test. Since your partner has HSV 1, that’s a consideration. It is possible that the lesions you are describing are HSV 1, though the timing of shaving has me leaning a bit more in that direction. Even if you did a confirmatory herpes western blot, which is far more sensitive for HSV 1 than the screening test you did, and you were positive for HSV 1, that doesn’t mean these bumps are caused by HSV 1. Does your current girlfriend get cold sores? I am a little bothered by your comment that the bumps changed into sores. It is good to hear that neither doctor who visually examined you thought your bumps were herpes.