I think the odds are really low, honestly. If I were you, I would live with the test results as reality, and if I developed some kind of lesion, I would have PCR swabs on hand to get it swabbed right away. Letting something that happens once every 18 months guide your life too much, in the face of negative tests, may not be the best way to life a happy life. You are bound by the reality of the testing available. That’s true for all of medicine, actually! When you may or may not have a condition that the majority of the US population has, things could honestly be worse. You might want to take a step back and try to view your situation from a more objective position. I think it might help.