Kolkata has a lot of pollution and i advice you wear a face mask to protect yourself first. And for the running nose and sneezing i suggest you steam inhalation and any other home remedy you know. You may not worry yet.

Maintain optimal humidity. If you live in a damp climate, talk to your doctor about using a dehumidifier. Prevent mold spores. Clean damp areas in the bath, kitchen and around the house to keep mold spores from developing. Get rid of moldy leaves or damp firewood in the yard. Clean regularly. Clean your home at least once a week. If you're likely to stir up dust, wear a mask....