Hello, Headache associated with sneezing and yellow mucus discharge is commonly caused due to common cold, allergy or sinusitis. Since you are also having yellow mucus discharge, its indicative of bacterial infection. You are suggested to use a humidifier, take steam inhalation to get rid of snotty nose. You can take non sedating antihistamines to avoid allergy. You need to take a course of antibiotic, like Azithromycin or Amoxicillin to get relieve faster. Take warm beverage and avoid eating frozen food or taking cold drinks of any kind. You should feel better after taking medicines. To get relief from headache, you can take Acetaminophen or Naproxen, one SOS when required. Take care. Hope I have answered your question. Let me know if I can assist you further. Regards, Dr. Nupur K., General & Family Physician