What Causes Chest Pain And Shortness Of Breath?

My son, age 17, has been having chest pains and shortness of breath lately. He has had 2 episode where he suddenly rises and his chest is in pain and he has difficulty breathing and the other where he was playing basketball in the school gym briefly and his chest started hurting and he had difficulty breathing. He just had a doctor's visit 2 weeks ago and his doctor said to monitor this. The pain is usually short lasting less than a minute with the difficulty breathing lasting the same. My son also has epilepsy, but we have never seen this symptom with a seizure. My son never lost conscience during these 2 episodes.