I just had a spicy meal, and a glass of green tea (i have noticed a sensitivity to caffeine). Suddenly, my upper lip started twitching. When I lifted my upper lift, for observational purposes, I noticed the veins pulsing. I am 40 years old, today, 5'10" and 150lbs. I have been diagnosed with Generalized Anxiety Disorder, and have had a stressful day. What might be the cause of this?