Brief Answer:
You should be clinically assessed by a doctor thoroughly...

Detailed Answer:
Hello and Welcome to 'Ask A Doctor' service,
I've gone through your query in detail...

Well, the difficulty in breathing itself can cause heartbeats running high...However, it should never be taken lightly and you should get examined by a physician or an Internal Medicine specialist in the first place...

Considering the present pandemic situation, it'd be fair to recommend that you should get clinically checked up without any further delay...

In case there's any history of travel in the past 14 days or any recent exposure to any suspected Coronavirus patient, you'll also be needing complete self-isolation for at least 14-28days...

-Wear face mask all the time (esp. while going out),
-Use disposable tissue paper, if at all there's any sneezing/coughing and strictly discard them to the trash immediately,
-Maintain strict hand hygiene by washing the hands with soap and water for at least 20seconds before and after touching any objects,

-For the headache, you can take Tab. PARACETAMOL 650mg after some food for the time being (can be taken up to three times a day)
-Avoid any body-contacts with others,
-Keep a distance of 3feet from others as well...

There are numerous causes (starting from lung and upper respiratory tract infection, bone and muscle infection, some noninfective heart-lung related pathologies, etc.)... A battery of investigations (e.g Complete hemogram, metabolic profile, sputum microscopy, and culture sensitivity, CRP, ECG, Chest X-ray, specific coronavirus testing as well) may also be needed to perform based on the clinical findings... Treatment/management can be decided accordingly...

Not to worry but don't delay this either, go ahead with the check-up and proceed thereafter...

Take Care
Kind Regards

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