While the only real way to confirm if you have COVID-19 is to get a diagnostic test done (RT-PCR/ Antigen), another way to distinguish your symptoms from that of the virus infection that’s currently raging across the world is tracking the symptoms. Keep a lookout for the symptoms you may be getting in the early days. For example, a low or mild-grade fever is one of the most widely seen symptoms with COVID-19, along with loss of sense of smell and body ache.
With pollution and seasonal allergies, problems like a runny nose, scratchy throat, red burning or watery eyes are experienced, which are not that fairly common in COVID cases.
Another marker to keep a note of during the pandemic would be that allergy and pollution driven symptoms tend to lower down once the exposure is restricted, unlike COVID symptoms, which take a different course of time to wane out.
Nonetheless, it would still be a good measure to self-isolate yourself and practice neccessary precautions until the time you don’t feel better.