Late Night Drinking

I'm not sure about some of you, but there are times when I just have to drink coffee. Well, tonight was one of those times. I finished drinking my second (large) cup of coffee a few minutes ago, and now I'm getting ready to go to bed. Strangely, I feel more tired now than I did before I had the coffee. Is it possible to build up a tolerance to caffeine? I guess so. Maybe this is just proof that I consume too much caffeine each day.