Every once in a while I feel my veins in my head twitch. Why? I'ma 28 year old female and I'm kinds scared..

Related to artery. This symptom actually happens to all of us at some time. It most likely is related to the arterial pulsation. The arteries which pulsate lie next to the corresponding veins. With changes in pulse rate, blood pressure and hydration the veins may dilate and reflect the arterial pulse of which we then become aware.