My husband has a uncomfortable feeling on his left rib cage when he takes a deep breath or yawns.it gets stronger at night and its been 2 nights now.

Pleuritic pain: Pleuritic pain can be concerning. Frequently benign, but there are few causes that need to be ruled out (i.e. Pulmonary embolism)! pleuritic pain is sharp chest pain that gets worse with deep breathing or coughing. Many conditions can cause pleurisy with infection being most common, but anything that inflames the pleural lining of lung may cause it. He should see a doctor!