Re-entry

During our trip to Germany, I drank bunches of coffee. The hotel where we stayed during the Octoberfest outing had a Starbucks. Care Bear has an awesome coffee maker that Cuddle Buns and DSIL kept flowing until about lunch time. (I think they were perhaps creating their own drinks with it. I was drinking it straight.) Yesterday, though, we left the house at about 6am Frankfurt time (11pm on Saturday Houston time) to catch our flight. I had one cup of coffee. I bought a Coke at the airport that was hot and consumed about half of it. By the time we landed yesterday at 3:30pm, I had downed maybe two little airplane cups of Coke. This morning, at 7am our time.....2pm - a whole day and a half from my last cup of coffee by my body time...I awoke with a massive caffeine-withdrawal headache. Perhaps it is time to cut back?