Hi. I can understand your concern.
Ideally ecg and 2d echo should be done first in your case. If both are normal than no need to worry for heart diseases. O it could be
asthma.Asthma is most common allergic disease which is not a curable disease but definitely controllable, by controlling the same you can lead a symptom free life. Usually presents with cough,
wheezing,
difficulty breathing and
chest tightness. If not treated appropriately can be life threatening.So better to
consult pulmonologist and get done clinical examination of respiratory system and PFT (Pulmonary Function Test).
PFT is needed for the diagnosis.
It will also tell you about severity of the disease and is based on severity only.
You may need inhaled bronchodilators and inhaled corticosteroid (ICS)
Don't worry, you will be alright.
Hope I have solved your query.
Wish you good health. Thanks.