It sounds like you are experiencing a sinus headache, likely caused by congestion from a cold. To relieve the pain, you can take an over-the-counter pain reliever like acetaminophen (paracetamol) or ibuprofen. To address the heavy, 'accumulated' feeling, an oral decongestant (like pseudoephedrine) or a nasal saline spray can help clear your sinuses. Warm steam inhalation and staying well-hydrated will also help loosen the mucus. Please consult a doctor if your symptoms worsen, you develop a high fever, or the headache persists for more than a few days.