Brief /random shooting pain across top of head, just right-of-center. have awful posture, & it started with a awkward neck movement. no other symptoms?

Cervicogenic Headach: You could be having cervicogenic headaches. They are typically referred from the neck to the head but I have seen patients having symptoms of head pain which refers to the neck, shoulders and arm. You may require a combination of physical therapy, posture training and short term medications. Pcp might be a good starting point.