My 9 year old son has been sick a few times in his life. 3 days ago he had a bad fever, vomiting, body aches, etc. He was much better after 12 hrs of sleep and ate a bowl of chicken soup that stayed down. The next day he was stuffy so he took a childrens allegra, which helped. However, when he lays down to go to sleep he begins to cough and quickly it becomes an out of control cough which induces vomiting. Today he was fine all day except for the allergy symptoms, and at bedtime the coughing followed by vomiting. Ibelieve he has a post nasal drip he doesnt know how to cough up, hence the vomiting. He is drinking alot of Smart Water with electrolytes, good meals, allergy medicine, etc. but nothing is working to thin out the mucus that I think is the culprit. Do I rush to the ER with no fever or body aches? I dont know what else to do....