The happiness in a cup of coffee

After memorizing stupid vocabularies, I felt a little bit tired. Countless impertinent thoughts occured in my brain and I had to overcome the hardness. Finally I went out of the studyroom and approched a bending machine.
And I choosed milk coffee, though I don't drink coffee because I'm very sensitive to caffein. After sipping a coffee, nonsensically I felt really happy. Because of sugar in the cup of coffee? or other reasons? I'm not sure, but I can certainly say that the taste of the coffee was the best among what I has eaten ever.