I'll go out on a limb here and say that a giant cup of sugared tea is the culprit. I can drink tea before bed, but black tea and sugar combined is probably not your sleep friend. Really, the sugar is probably the biggest issue.
I used to drink an inordinate amount of coffee, to the point of compulsion. I am a former smoker and still find myself reaching for the java when things get tense. Well I finally had stop having coffee after 6pm, then 4pm, etc until now I don't drink any caffeine after 1pm. I find that I sleep much better these days. I don't know what the half life of caffeine is but I think it sticks with you for several hours. Nicotine seems to not effect me but I also don't usually smoke after 8pm.
Not at all, unless you just smoked a big bowl of beacon extra and with your heart pounding nicotine through your veins decide to read through this thread because you couldn't sleep.. 8O
Crashthegray, your theory may be very correct, shall keep doing some experiments down the road, should to be said, I'always had some problems to get a sleep quick, especially early at nights, beforedays I was working on three shifts,most unconfortable I felt when I had to be on duty starting at 6 morning,