If you have been coughing a lot for 2 weeks and sometimes vomiting because of it, it could be caused by mucus dripping from your nose to your throat, irritating it and triggering the cough reflex. To help reduce the mucus and improve your symptoms, you can try using a Sinus Rinse™ treatment twice a day for at least 5 to 7 days. Other suggestions include elevating your head while sleeping, taking honey lozenges, or using cough syrup. If the cough persists after a week or if a fever returns, it's best to consult a healthcare professional.