Thanks for writing your query.
After reading your post, I would like to advise you that you should get yourself examined and investigated by a Cardiologist.
Following investigations will be helpful :-
3. Complete Blood Count(CBC).
Also monitor your heart rate and blood pressure.
Also monitor your temperature as heart rate can be increased in fever.
Medication can be planned according to the reports of the above investigations.
Anxiety also result in increased heart rate
You should go for yoga and meditation
to deal with anxiety component, if any.
Also lead a positive life.
I hope this is helpful to you.