The one sided facial pain could be due to sinusitis, as it is accompanied by
nasal stuffiness and sometimes a post
nasal drip. It could also be due to tooth infections, impacted tooth or skin infections. The others are migrainous headaches and those caused due to brain disorders, disorders of the eyes , neck or ears to name a few. To find a cure you need to consult your primary care physician for proper assessment. In the meantime take OTC naproxen for relief from pain. Regards.