I just went through this on vaca (ETA: caffeine withdrawal, not ramping up caffeine). Forgot to buy coffee for the cabin, so had no caffeine on Tuesday. Headache lasted until my third cup of coffee on Wed. I feel normal again now.
I gave up coffee when I was pregnant, and for a year after while BF. Also for like two weeks after college, until my family begged me to drink some darn coffee already!!!
Personally, I know I have an addictive personality, so I'd rather it be coffee than something else.