My mother has undergone a total thyroidectomy two years ago and also taken iodine radiation treatment then after. And has a regular dose of tablets now. But now since a few months she suddenly gets uncomfortable and can't breathe, with the severe chest pain and dizziness, she becomes restless and feels suffocated so she tries coughing but there's no discharge of anything and severe choking sensation this causes terrible headache simultaneously. It's starts kind of an attack and lasts for very long time like more than a couple of hours or so. Please someone suggest me the course of action. Where to visit. The doctor's haven't prescribed any medication to sort this problem yet.