What Care Can Be Done For Cough And Shortness Of Breath After Getting Treatment For Fractured Ribs?

Can pneumonia come back suddenly ? I was diagnosed with it in both lungs the 6th of June. I went to the urgent care facility because my ribs & chest hurt really bad. They x-rayed & found i had 3 fractured ribs on the left side & 1 on the right. The prescribed the strongest antibiotic you can take with being in a hospital. Ribs were almost healed last week but coughing & shortness of breath started again. I m 55 yrs old & smoke have for over 20 years but the past few weeks i have not smoked more than 3-4 cigarettes a day. Thank you for your time.