Once, I had a very unpleasant pulsing headache after drinking a superfluous dose of highly concentrated black tea. I wasn't able to get rid of that until I fell asleep. Since then, I made up my mind not to abuse caffeine. Sometimes that's hard to avoid drinking much tea, especially feeling worn-out beginning from the morning. But, I can always remind myself of my terrible experience, and refusal from a dose of tea doesn't already seem anything impossible.
Who faced the same?