Thanks for providing more information.
Meloxicam is a NSAID with analgesic and fever reducer effects so it can help you in relieving headache.
Apart from this,as you have sinus infection so your headache can be associated with it.
So you should do saline gargles and menthol steam inhalation.
Also hydrate yourself with warm liquids.
Take OTC Claritin.
Use a humidifier in your room.
Elevate your head side of bed.
If your symptoms'll persist more than a week then consult your regular doctor for further evaluation and management.
I hope this helps.
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