I Have Been Coughing For About 3 Weeks Now. It

I have been coughing for about 3 weeks now. It started with a cold, then sinus type infection, now in my chest. It's worse at night when I lay down. In the morning from the time I get up around 7 until 10, I cough up big globs of yellow & green phlegm with sometimes chunks of chicken-like pieces. I have been using Mucinex during the day and I have been taking Robitussin at night. Do I need an antibiotic to end all of this?