👉 Headaches are a common symptom that can be caused by various factors such as stress, dehydration, or certain medications. They can last for several hours and may lead to discomfort, pain, and sometimes nausea. There are many causes of headache, including infections (such as sinusitis), overuse injuries, medications, and hormonal changes. It's important to seek medical attention if you experience severe headaches that persist for more than two weeks or if they interfere with your daily activities.