I Developed A Bad Cough The Past 2 Days And

I developed a bad cough the past 2 days and thought my issue may be due to drainage from allergies, although I have never had allergy issues before. I have taken Allegra-D the past two days and ever since I have a strong smell of ammonia in my nose and no appetite. When I do eat I taste ammonia. Could it be the medicine? Or do I have a infection in my chest even though my cough is a dry hoarse cough?