Sinus Medication Solution

i have had a headache for nearly 4 straight days….i had 2 sinus infections in the last 4 months but they were different than this , i had colored nasal and phlegm discharge. ive tried everythign for this headache and i have an ENT Appt on tuesday….but this headache wont go away, im pretty sure its nothing too terribly serious, just wanna know if u can have a sinus infection without the crud or fever.