Hi. Welcome to Healthcaremagic
You have multiple symptoms. Cough
and postnasal drip are clearly connected. Upper respiratory tract
infection cause these symptoms. Even acidity can cause cough but it happens in severe cases.
I suggest you get Sinus X ray
and chest X ray. After X ray results consult MD for evaluation. Get A course of antibiotics for 1 wk. Use Pantop for acidity.
Regards, Dr. Jagdish