Could Severe Cough Be The Symptom Of Persistent Influenza Virus?

Hi, I had a bad viral infection and a horrible hacking cough for about 5 days. it started on Dec. 31, and on Jan. 4th I saw a Dr. who said it was a viral infection (get lots of rest, fluids etc.)... then 5 days later, my cough was getting worse, so i went to my family Dr. and she said I had pneumonia (viral). That was last Thursday. I had over a full week of rest, and I only feel somewhat better... I have some energy, (not as much as normal), but I still have coughing attacks where it is hard to breathe. I am very behind at work, and i know i can spend some time doing report writing. I have already missed a full week of work, and am wondering if it's okay to go back to work... I am coughing a lot, so i guess its important to know if the virus is still contagious?