Hi, Facial pain on bending is traditionally thought to be diagnostic of sinusitis but this is non specific as many types of facial pain and headache are made worse by this action. Various causes of similar headache are 1. Dental pain Any sort of dental infection,malocclusion or temporomandibular join pain can occur like this. 2. Tension headache 3.Neuralgias If you have associated sinusitis symptoms, like nasal discharge, post nasal drip,hawking sensation,coughing out sputum, then it could be sinusitis. Also, it s said that improper ventilation of sinuses due to obstruction of its natural openings could also lead to headache. First thing you have to do is to do steam inhalation. Take adequate rest. Avoid alcohol. If frank symptoms of sinusitis arises, you need to start on antibiotics. In this stage of symptoms, conservative management is better. In between, consult a dentist to rule out any dental problems.