Brief Answer:
Clinical evaluation and diagnostic tests needed.

Detailed Answer:
Hello and thanks for using HCM.

I have read your query and understand your concerns.

Feeling lightheaded, short of air, chest pains after physical effort means that oxygen is lacking to brain and body and circulation system is incapable of fulfilling increased demands during physical activity.

Conditions that may cause such symptoms include heart conditions ( high blood pressure, enlarged heart, heart valves incompetency), pulmonary disease (bronchitis, pneumoniae, pulmonary fibrosis etc.), low thyroid gland function and anemia.

Since you didn't experienced any health issues in the past, you need a clinical evaluation first and appropriate tests guided by clinical findings.

I suggest you to discuss with your primary care Doctor about above mentioned possibilities of your concerns.

Hope you found the answer helpful.

Take care.

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