i have gone through your problems.
as you have normal bp,normal thyroid
profile and you are non smoker and non alcoholic it is unlikely that you have cardiac problem.
but you inform me about your blood sugar level.
do ECG,holter monitoring to document any arrythmia
is present or not.
but your symptoms tell that most probably you are suffering from anxiety.
remove anxiety by doing yoga,meditation
.your problem will resolve.
if symptoms persist,do above mentioned tests and consult a cardiologist
i think my advice will help you.