I'm really worried about something I just found out. Last year, I was in a car accident, and nobody told me anything about my chest x-ray results. I looked at the report today, and it mentions things like biapical pleural thickening, perihilar interstitial prominence, and mild hyperaeration. I have no idea what any of this means. I was fine until recently, but now I've started coughing up phlegm, and I get short of breath when I walk up stairs, although it goes away quickly. Other than that, I feel healthy. Can you help ease my mind and tell me what I should do next?