Stress is the most commonly recognized trigger of headaches. It can be physical or emotional. It can be good or bad. It is an unavoidable part of life. Events causing emotional stress can trigger a migraine headache. Migraine sufferers are thought to be highly responsive emotionally. In times of emotional stress, certain chemicals are released that provoke the vascular changes that cause a migraine headache.

Reference :  https://headaches.org/2007/10/25/stress/, july 08th,2019