Symptoms. Symptoms of a pulmonary embolism are sometimes preceded by swelling and pain in the leg, as the clot almost always comes from a deep vein in the patient’s leg. Other symptoms can come on suddenly. The person has sudden difficulty breathing or shortness of breath. They may faint, feel a pain in the chest and have a rapid heartbeat. They develop a low fever and a cough that sometimes brings up bloody sputum.
