I have been very concerned about my 14 year old son who has had a cough and a hard time breathing often followed with him gasping for air. I have called paramedics 2x taken him to his primary physician and took him to E.R. last night. They told me he had strep throat on top of a bronchial virus. He was given a single shot of penicillin which should of taken effect within 24 hours according to hospital nurse and doctor. I am concerned because I keep reading about whooping cough and it sounds like he may have this. What should I do ?