Hi, welcome to the forum, it is important to rule out respiratory system
dyspnea (breathlessness) from cardiovascular
dyspnea. Or else you may have more than one problem contributing to the breathing discomfort.
The most common causes of dyspnea are asthma, COPD, interstitial lung disease, and cardiomyopathy, valvular disorders, pericardial diseases, anemia etc.
You need to undergo pulmonary function tests like spirometry, chest radiograph and ECG to rule out the cause.