Im a recent uni grad and in the last few weeks prior to my exams I must of drank 4-5 cups of coffee and 3 cans of monster a day and countless bottles of Mountain Dew and tea, this continued for over a month until very recently when I realised how much caffeine I was consuming daily, and so 3 days ago I went cold turkey- no coffee, no energy drinks not even tea.
For the whole 3 days I was in actual physical pain- my joints ached like they'd been pulled, my skull felt it was cracking and I actually broke into cold sweats at about 10am.
Im no longer going cold turkey but instead have managed to cut it down to one cup of coffee and 2 cups of tea, I still get the aforementioned symptoms but too a much lesser degree.
To answer your question more directly, I have one hell of an addiction to caffeine.