Why does the location of my headache shift when I move my head?

Other symptoms? Worsening headache with lying flat can result from accumulation of excess water in the brain (condition causing poor cerebrospinal fluid-csf flow). Worsening headache with standing can result from abnormal leakage or escape of csf. Would get checked by your doctor.
Headaches. Headaches from sinus pressure or muscle tightness can seem to migrate to other areas with movement.