There are three possible cases of pain in the back of the head after blowing air conditioner: 1. Migraine attack induced by blowing cold air, patients often have a history of migraine, migraine can be manifested as deep swelling and throbbing pain in the back of the head, often triggered by factors such as blowing cold air, staying up late, drinking alcohol, etc. The attack usually lasts from several minutes to several hours. 2. Occipital neuralgia, the occipital nerve is located on the left and right sides of the back of the head, in the subcutaneous part of the basilar membrane. The pain is usually limited to the extracranial muscles and subcutaneous pain, manifesting as paroxysmal throbbing pain, stabbing pain or electric shock-like pain, pulling-like pain. 3, myofasciitis-induced soreness and swelling pain, which is also caused by blowing and cold, resulting in chronic inflammation of the myofascial membrane, with diffuse swelling pain when pressing the local area.