I don't think it's just a question of the drugs getting out of your system; it's your habit of taking them that you have to address. You have become psychologically dependent on them (and tea drinking, smoking, etc.) so the pains and problems may not go away just as quickly as one would think they would until you address the underlying problems that started the self medicating in the first place.

I would go at it the other way around; concentrate on exercise and diet first and let the meds and excesses fall in line from there. As you've learned, too much tea/caffeine will give you headaches (and withdrawal from caffeine, a drug, is fierce and will give you a headache when you're completely off it for about a week!), etc. I think it is going to be a long, bumpy ride for you