I'm asthmatic w/ sleep apnea. I had rib pain after sinus/bronchitis (coughing). Xray showed new lung scarring. Can this cause me trouble in future?

How do you know. A new change on the cxr may be or may not be a "scar". Expert consultation is indicated.
Lung scarring. It most likely will not cause a problem but it depends on the extent and location of the scarring. Long term scars of the lung may be associated with an increased risk of developing into carcinoma particulary with a history of smoking but this is relatively low incidence.