What Causes Headache?

Hi my name is Fabrina from Seychelles.I've been having severe headache on Lt side radiate to the ear n nose,admitted rehydrated but still no cure,had fever before,taking paracetamol 4hrly andaccording to an ENT I have polyp on the right side and both maxillary sinusitis,according to an x-ray I did,but she is not really clear on the details(language barier).Am 20 wks pregnant and am really scare.I need advice.