My 23 Year Old Son Had Terrible Stabbing Chest Pain

My 23 year old son had terrible stabbing chest pain two days ago. He also had numbness on his right side. At the emergency room they did ekg and xrays and said it was probably a chest wall spasm. Today he has numbness in both arms again. He called the emergency room and they said to take some aspirin which he did and he says he is feeling better. What should he do?