Thanks for your question on Health Care Magic.
I can understand your concern.
No need to worry for heart diseases if your 2d echo at regular intervals is normal.
Shortness of breath and
chest pain are also seen in lung diseases like bronchitis and asthma.
So better to
consult pulmonologist and get done clinical examination of respiratory system and PFT (Pulmonary Function Test).
If PFT is suggestive of obstructive airway defect than you may need inhaled bronchodilators and inhaled corticosteroid (ICS).
But if PFT is normal than no need to worry for Pulmonary diseases.
Than stress and anxiety related symptoms is more likely in your case.
So avoid stress and tension, be relax and calm.
Consult psychiatrist and discuss all these. You may need
counselling sessions.
Don't worry, you will be alright.. But first rule out Pulmonary causes.
Hope I have solved your query.
Wish you good health. Thanks.