Are these IgG tests?
If they are, then they are likely not false positives at the numbers you got, unfortunately.
Hsv1 rarely has false positives, and hsv2 false positives are usually below 3.5.
Herpes outbreaks can often be misdiagnosed as yeast infections - did your doctor actually test you for yeast? Since you have hsv1 (which is most likely a long established oral infection like about half the adult population), it would tend to make your genital hsv2 infection milder. Yeast infections can cause a lot of skin irritation, leading to the confusion.
Has your girlfriend seen her results? I ask because quite often, people think their STD testing includes herpes testing, and it doesn't, even if they ask for it specifically, or say they want to be "tested for everything". Many doctors are very uneducated about current herpes testing.
How long have you been together? Have either of you been with other partners prior to this relationship?
You should read the Herpes Handbook at https://westoverheights.com/herpes/the-updated-herpes-handbook/ - it's free, and written by Terri Warren, one of the world's leading experts on herpes.
Let us know what questions you have.