Headache is one of the most common complaints in primary care. While most are primary headaches, changes in headache pattern, inadequate response to treatment and increased analgesic use are red-flag features suggesting secondary causes.A 45-year-old woman presented with a one-year history of progressively worsening headaches, now occurring 4–5 times per week and waking her from sleep. Despite recent neurology evaluation and adjusted migraine prophylaxis, symptoms worsened and daily analgesic use increased. Neurological examination was normal. Due to red-flag features, she was referred to ENT for neck–carotid evaluation. CT angiography showed a 56×25 mm hypervascular mass consistent with a glomus tumor. She underwent embolization and surgical excision.The only presenting complaint was headache, without focal neurological deficit or otologic symptoms. A rare glomus tumor was diagnosed solely through primary care clinical reasoning based on red-flag symptom recognition rather than classic tumor findings.Change in headache pattern requires re-evaluation. Analgesic overuse and failure to improve despite recent specialist assessment should prompt search for secondary causes. Family physicians play a key role in early identification and timely referral, improving outcomes.Paragangliomas are rare and often present with nonspecific symptoms. Early recognition of red-flag features in primary care prevented diagnostic delay and facilitated appropriate multidisciplinary management. This case emphasizes the educational value of structured decision-making in common symptoms such as headache.Early recognition of red-flag features and timely referral in primary care can prevent diagnostic delay and reduce morbidity. This case highlights the critical role of family physicians in identifying secondary causes in patients presenting with common symptoms such as headache.