blinding headaches when standing after sinus infections

I get these blinding throbbing headaches when I stand after I have been sitting for a long time but only after I have sinus infections. If the infections has lingered, like this one, it's right on my temples. I have not been diagnosed with HBP but my blood pressure has been 120's over 80's. I feel like I am gonna pass out from the intense pain but I am not dizzy. If I lay my head down, they go away faster.

[Dr Santos]

Hi,
How are you? Sinus headaches present with pain that often increases in severity throughout the day.  Migraine and cluster headaches are often misdiagnosed as sinus in origin. It is important that the underlying cause such as infection, nasal polyps, anatomical deformities such as a deviated septum, be managed. Antibiotic treatment, decongestants, and even surgical drainage may be indicated. If it persists, have this checked by your doctor for proper management. Rake care and regards.