Need to know what kind of whole it is pretricuspid or post tricuspid, generally the size you mentioned is small hole only looking at your age. Generally infective endocarditis prophylaxis is requird if it is a post tricuspid shunt. Your present symptom scenario is also needed to allow heavy exertion activity. Also need to see it isometric exercise or isotonic
Next Steps
Consult a cardiologist, fresh echo would be needed