It's important to pay attention when a headache feels significantly different or much worse than your typical headaches. Key warning signs that warrant immediate medical attention include a headache that is sudden and severe, often described as the "worst headache of your life." Other red flags are headaches accompanied by new neurological symptoms like weakness, numbness, difficulty speaking, confusion, or vision changes. A headache with a high fever, stiff neck, rash, or seizures also requires urgent evaluation. Doctors typically ask about the onset, intensity, associated symptoms, and any recent head injury. They will often perform a neurological exam. Always seek urgent care for any sudden, severe, or unusual headache, especially if new symptoms appear. When did you know it was time to seek help for a "different" headache?