My Wife Had A Partial Thyroidectomy In Nov Of Last

My wife had a partial thyroidectomy in Nov of last year. (Right side) Now, when she drives her car after 10 mins she develops pressure pain on the side that part of her thyroid was removed. She also gets nauseous and has a stabbing pain under her arm near her breast around the second rib. She says it's like a stone bruise pain under her arm and is painful to touch and affects her breathing some. 15 mins after she stops driving her nausea is gone and the pain under her arm is gone. The pressure in her throat ( right side) remains til next day. As long as she doesn't drive there are no symptoms at all. As soon as she starts driving it begins all over. Her surgeon said it was muscle strain but to me that just doesn't add up affecting her on her right side ribs under her breast. Her thyroid count is normal. No other symptoms unless she drives her car. We are confused.