Only about 5.5% of people who do the IgG antibody test have values in the low positive range that could be false positives. I personally wouldn’t let that stop me from testing. If you get a low positive IgG value, we can order a western blot for clarification.
If you have genital HSV , it could certainly be HSV 1, and that’s best detected by western blot, better than the IgG.
The canker sores in your mouth and genital symptoms are likely NOT connected.