Hi. Noted your history of visit to ER but the problems of tired heavy legs, shortness of breath remains the same, EKG is said to be normal. Since you have already visited ER you must have been given some medications that you should continue so that you gt some symptomatic relief. I would advise you to go to your Primary Doctor for proper clinical evaluation, examination and relevant investigations of blood, urine and stool. Clinical examination will also see for any Asthma, Respiratory infection or so as a cause of shortness of breath and get you treated accordingly. Heaviness with tiredness of legs can be due to primary respiratory issue and proper oxygenation and treatment may help for a relief. Take rest, take plenty of warm fluids orally and continue medications as would be advised by your Doctors. If required get fully investigated and referred to a Specialist for further evaluation and management. Hope I have answered your query. Let me know if I can assist you further. Regards, Dr. T. Chandrakant, General Surgeon