Good evening sir. Well from what you describe doesnt sound normal after surgery at all. Rather you should have been back to normal. But what i can say is u need a detailed work up. Kindly consult your cardiologist ones. He needs to look into ur medications( whether they are causing side effects) or there is some other problem like thyroid
or sone lung/heart abnormality going on. Do let me know for further queries. But dont dekay your appointment.