Headache and nausea can be caused by various common conditions including migraine, tension headache, cluster headache, and neuralgia. Thus, headache and nausea are not necessarily indicative of a cold. It is important to check the body temperature and other accompanying symptoms. If a patient experiences a slight increase in temperature, such as between 37-37.5 degrees Celsius, accompanied by symptoms like sore throat, nasal congestion, runny nose, and sneezing, these could suggest that a cold is causing the headache. A cold can also lead to nausea, especially in cases of gastrointestinal flu, where the illness may begin with headache and vomiting. Therefore, headache and nausea are not definitive signs of a cold. If respiratory infection symptoms are present, it may indeed be caused by a cold, and rest, increased fluid intake, consumption of vegetables and fruits, and taking cold medications if necessary would be advisable. If the headache is severe, appropriate pain relief medication should be administered.