Are you suffering from chronic sinusitis?
Do you have allergies?
Where is the headache located exactly?
Did the headaches begin suddenly?
For how long you are experiencing headaches?

i had gamma knife in may for trigeminal neuralgia was really messed up and ended up with different neurosurgeon he did mvd now i cant lay down or sleep for more than an hour because ear, behind nose and pressure in the head wake me up in terrible pain. once up and take something for pain it subsides. at first i thiught it was bad tooth but tooth doesnt hurt all day long. any info or help would be welcome. thank you, paxajan

My similar symptoms are due to muscle pain caused by a damaged TMJ. I used to get pain after a couple hours of standing up, and now after surgery I get pain after laying down - only on the back, when I turn my head to the side it subsides. The pain accumulates, is deep dull muscular and it took a really long time to figure out what it was - it covers the whole half head and neck and is present behind the eye and above and in the teeth.

Surpisingly, the most effective treatment was Botox, and cheap injections of temporary pain relievers also helped (which may pre-indicate whether Botox would be effective for your cases).

Stress greatly increases the pain. Even for no reason if something stressful happens the pain kicks in immediately.