smart at (something)
1. To experience a sharp but superficial or fleeting pain caused by something. "I wish I had brought my work gloves with me," I said to myself, my bare hands smarting at the abrasive surface of the cinder blocks I was hauling around. Her entire body was burned so badly by the sun that she smarted at the slightest movement.
2. To experience acute mental or emotional distress. I smarted at his callous implications that I had somehow been responsible for Tom running away from home. She smarted at the recollection of the foolish way she had behaved during the interview.
smart at something
to suffer the pains of something. Over an hour later she was still smarting at his cruel remarks. For many days Ted smarted at the scolding he got.