Yes, it is possible that your coughing is causing you to feel nauseous. It is important to address any congestion in your nose as it could be contributing to your symptoms. Using a saline solution like Hydrasense or Sinus Rinse can help with nasal hygiene and prevent mucus from causing coughing and nasal congestion. Applying Vicks ointment to your chest or back may also provide relief. Be sure to consult with a healthcare professional for personalized advice on managing your symptoms.