Most common symptom in Pulmonary embolism is -

Dyspnea is the most common symptom of PE,and tachypnea is the most common sign.Dyspnea,syncope,hypotension,or cyanosis indicates a massive pulmonary embolism;whereas pleuritic pain,cough,or hemoptysis often suggests a small embolism situated distally near the pleura. Reference:Harrison' s medicine-18th edition,page no:2172.