I had lesion on my vaginal

I felt a sore on my vaginal last 3 days ago. Yesterday i found there is a blister, lesion on my vaginal, this never happen before. Went to see doctor, he suggest I take blood test for igG, and igM. I read some post mentioned to take the test after 3 months? 

It just only 1 ulcer like and a few small blister like around it. Infected area is about a cm.

IgM is worthless for herpes, and IgG is only conaideted conclusive at 3 months (but a good indicator at 2 months). With a blister, your doctor should have ordered a swab test. If the blister is still new, go back and demand a swab test. I don't understand why so many doctors fail to order swab tests for their patients when they suspect herpes and lesions are present to swab. The blood tests are indirect and have limitations.

*considered* conclusive. No idea how that ended up so different in my above post!