At your index value, there is probably a 70% chance that this is a false positive (30% chance it is accurate.) per the CDC recommendations, you should have a good confirmatory test – the best is the western blot. I’m afraid I can’t make an assessment of how likely this is to confirm without a whole lot more knowledge about your sexual history, the percentage of time you use condoms, the total number of sexual partners you’ve had, etc.
Terri