I've been using Afrin on and off and recently went off of it because of the rebound effect. What does the test indicate though? Afrin will clear your nose regardless of allergies or not. I don't see how this test would tell me anything.
Assuming you’re cleared for allergies, it can show that it’s positional. I wouldn't use Afrin on a regular basis, or even more than two days. Try corticosteroid like flonase instead
Also hepa air purifier, vacuuming/avoding carpets, and replacing and continuously running HVAC filter/fan has helped.