We believe it is a drop in estrogen that triggers this. Seventy-five percent of women go through this. Avoid birth control pills when possible. We advise people to get enough sleep, eat right, etc. Caffeine is a drug and when used on a daily basis, it can cause rebound headaches.
Regular use can make a person with migraines dependent on caffeine.
My friend grinds his teeth at night and wakes up with headaches. Grinding one's teeth can cause tension headaches. You should see your dentist and consider a bite block. Many medications can cause headaches. With your doctor's advice, taper off of them and maybe substitute them with something else to see if your headaches improve.