I've had a cough for 3 weeks. What do I have?

I started getting a cough 3 weeks ago. It started as a dry cough, but by the end of week 1 it was mucusy. During week 2, I woke up around 1 o'clock in the morning having a coughing fit. I felt my throat contracting, but not closing. This lasted for about 30 minutes. Cough drops would not help my cough. I went to the doctors end of week 2. She said I had allergies, so she told my to take Claritain and some tea with buckwheat honey. This didn't help (except for clearing the mucus in my throat a little bit). By the end of week 3, the cough has become really mucusy and now my snot and mucus in my throat is taking a yellow-green tone to it. I don't believe I had allergies, but I believe it is bronchitis. Is this right?