If your heart is not comfortable on what you’re doing, definitely have that checked out fully. You could have a clot or some plaque buildup in an important place, a ventricle could be thickened... lots of things could be very wrong and you end up dead at a young age, younger than I am for sure, of a heart attack, myocardial infarction, ventricular fibrillation... something cardiac arrest inducing. So see the docs...