If i need a sinus x-ray do i go to the hospital and ask?

No: You call your GP or go to a walk in clinic. They will explain why you do not need a sinus xr and help you with the problem. A sinus x-ray is not needed to diagnose most all sinus problems so it is a waste of time of money. If you have been hit in the face or had some trauma then a CT of the face would be more useful.

Need examination by: Tests like X-Rays have to be ordered by a doctor who must first examine you to determine the need for doing X-rays ( of your sinuses). You need to go to see your primary care doctor or go to a ENT specialist. The hospital will not do an X-ray unless it is requested by a doctor. Good luck.

Ask your doctor : CT of the sinuses may be more appropriate although depending on where you are and your health system you may only have facial X-rays as an option. They aren't that good at imaging sinuses. Perhaps see a doctor to examine and discuss what test is best for you