[header] How to diagnose pericarditis [title] Notice chest pain. [step] Chest pain is not something you ever want to ignore, so if you have chest pain, you should go to the doctor or emergency room, just in case. Try to take note of where, exactly, you're having chest pain, as well as if certain actions make it feel worse, such as coughing or lying down. 
[substeps] Chest pain associated with pericarditis is generally sharp and quick, not drawn out. Coughing or lying down will often make the pain feel worse.