Overall I think the points were fine and this is certainly an uncommon reaction. That type of sensation can come from nerve impingement in the neck, so you might have just starting to move this to the point where it created a different symptom. If the patient will return, after a couple treatments everything should be fine. Neck pain/stiffness generally responds very well to treatment.
Points-wise I would remove GB 21 and UB 10, add in GB 20, GV 20, GB 34, and UB 60. This, for lack of more technical reasons, to spread out the treatment energetically. Too many points at or near the area of concern, particularly in the neck/head region, can cause too much energy to ascend to the head and lead to some of these symptoms.