What Causes Persistent Cough Along With Pain In Upper Back And Chest?

About three weeks I had a bad sore throat but within a couple of days, I felt much better. I then flew across the country & developed a nagging cough. Now, three weeks later, my cough has gotten worse & I have a pain on my upper back as well as my right chest. I assume the pain is a result of all the coughing I've done. I also find that I don't have the energy level that I've always been fortunate to have. I'm not able to take a lot of medication & have used teas as well as homeopathic meds but am still coughing!