Is it possible to have meningitis without a bad headache and having a normal cbc ?

Yes: You can have an aseptic or viral meningitis without severe symptoms but the headache is usually more than mild. The much more serious bacterial or fungal causes of meningitis cause very severe symptoms including fever, chills, headache, stiff neck, altered mental status and seizures.

Yes: Meningitis is really uncommon if you not terribly ill. The only way to exclude it as the source of headache is to perform lumbar puncture. There are many more common causes of chronic headache. Rarely some fungal meningitis or neoplastic meningitis may not cause a headache. If you are you immunocompromised you may not mount enough of an immune response to have a headache.

Yes: Pts with some forms of viral meningitis may have confusion, problems with balance or memory, or unusual movements but never complain of a headache. Normal CBC is common in viral infections.