Cough that is Becoming Severe Over Time?

I have a cough that started out pretty mild last week. Around last weekend, it become a cough with a little more phlegm in it giving it that wet cough sound. The beginning of this week it continue to persist. Though cough medicine would stop it. Yesterday, I took some cough depressant before going to school. It did NOTHING to stop the coughing. Last night, I took NyQuil before going to bed. I didn't cough while sleeping, but before sleep and after sleep I was HORRIBLE! I just came back from school and the cough is really bad. It is multiple coughs in a row (3-8) and it starts out with a little phlegm then gets dry. I though it was pertussis but it really doesn't have the whooping cough sound plus I had my TDaP 6 years ago. My question is, is it pertussis or is it something else? My step dad is a smoker so I'm afraid it could be from second hand smoke. Asthma is also prevalent in my family. Any more information you might need just let me know. I'm gonna try to record it so you can hear it.