Since how long are you suffering from Headache? And where is pain mostly.i mean which part of the head?! And ist vomiting is relieving headache..??
It can be so many types of headache dear.so need to rulled out if you suffering from Long standing Headache.
In your case it can be possible of secondary headache which can be happen as a result of allergic reaction of your sinus which is mostly pain in the forehead.
Next Steps
Need proper history and examination for further diagnosis
Please use Nasal steroid sprays for you sinus
Antihistamines such as citrizine.and if there is sinus infection then might be u have to start Antibiotics to clear the infection and relieve your headache.