How to deal with bronchitis?

I don't know 100% sure if I have bronchitis, but I am displaying what I think are the symptoms. I have had this for almost 3 weeks now. I have been coughing up phlegm this entire time. At first it was clear, but then when it turned yellow, I went to see a doctor who prescribed me with an antibiotic, Zithromax, which I used for a week. After that week, the yellowness had mostly subsided, except for when I first woke up early in the mornings, which I believed was due to a build up overnight. The coughing and phlegm being produced continued, so I went to see my doctor again this Tuesday. He is now having me use Advair, which he said can be used to help treat Bronchitis type symptoms, not just asthmatic symptoms. I have been using it for about 2 days now, but it doesn't seem to be doing much. Please, how can I alleviate the over production of phlegm in my body as well as my cough. I have been drinking a ton of water, herbal teas, and taking herbal supplements, but this won't go away.