I go walking daily and my heartrate increases rapidly and i struggle to breathe at times (which was not a problem before). my heartrate takes long to normalize again and my breath takes longer to recover. ?

Eval: If you have new onset of chest tightness, difficulty breathing, cough and chest congestion please consider a consultation with your doctor. So you have fever,, feeling tired, muscle aches, headache, sore throat, chills, chest pain, nasal congestion, loss of taste or smell, nausea, vomiting, diarrhea?

Evaluation: Since your symptoms occur with exertion,I recommend a cardiopulmonary evaluation. Also, make sure you're not anemic. Cardiac physical examination,EKG, echocardiogram, treadmill stress test, outpatient heart monitoring of heart rhythm to be done. If no cardiac issues, consult a pulmonologist. Anxiety often causes symptoms at rest rather than with activities. Stress management would help this.