Yes, you can consult a pulmonogist if have symptoms of pneumonia.
Pulmonologists do perform specialized procedures to get samples from the inside of the chest or inside of the lung and they use radiographic techniques to view vasculature of the lungs and heart to help with the diagnosis.
You should consult a pulmonologist if the cough persists for more than 3 weeks, or if it becomes severe.
The lungs can heal over time, there's the initial injury to the lungs, followed by scarring but with time the tissue heals and it can take approximately three months to an year.