A shingles exposure would have nothing to do with your HSV 2 antibody test being positive.
And yes, one would expect that if you were infected with HSV 2, your index value would be higher by now. However, a few people simply have a true positive with a low index value. I had someone with a 1.16 index value confirm with western blot last week, so it does happen that these are true positives. That is why we (and the CDC) recommend confirmation with western blot for people who have an index value between 1.1 and 3.5 . These values are technically positive, but only 50% confirm as positive. The closer your value is to 1.1, the less likely it is to confirm with western blot.
If you decide to get a western blot, our clinic can help you. You do need confirmatory testing for a clear answer here.