Can my worst headache ever be bacterial menigitis?

Could be : Bacterial meningitis can cause a bad headache with neck stiffness, associated with fever, malaise and confusion. We usually associate the description of the "worst headache in my life" with an aneurysmal rupture causing a subarachnoid hemorrhage.

Yes: There are many reasons for you to have your worst headache. Meningitis is usually accompanied by other symptoms such as stiff neck, fever, altered mental status.