Sometimes doctors diagnose things "by sight" but herpes can look like about 100 other things - and 100 other things can look like herpes!
OH! SO true!
I am not a big fan of the current blood tests. The rate of false negatives is a bit higher than I am comfortable with. And, did you specifically ask your ob/gyn to do the bloodwork for herpes when you got pregnant? Because it is NOT typically a part of the screening. So just wondering if you asked for the bloodwork or if they did it b/c you mentioned herpes. The ACOG recommends that ob/gyns screen pregnant women for herpes by getting a history ("Do you have herpes?" that's it!) and by monitoring for lesions.
I know two moms who said that they had outbreaks during pregnancy that were misdiagnosed as yeast infections. So, when you are having those symptoms, it might be a good time to have your doc do a culture of your vaginal walls and cervix. I also agree with pp that 5-7 days is too late. Now that you are pregnant, your ob/gyn should be eager to culture ANY sort of outbreak as soon as it begins.
The "good news" is that IF
you already have herpes, your baby is pretty safe. The chances of passing herpes to your baby if you were infected prior to conception (or even during your first 2 trimesters) is only 1-5%. And if you are aware that you could possibly have it, then you can cut the risk down even more. The biggest risk and danger is to moms who contract herpes during the last trimester. So, I would suggest you protect yourself as if you have never been exposed (especially since your bloodwork is negative...but be sure those specific tests were performed).
My twins had neonatal HSV-1 so I learned an awful lot about herpes and pregnancy awful quickly. If you have any questions, I am happy to offer what I know.