Whenever one has been immersed in culture for a period of time, there is usually a culture shock of some sort that smacks you. Last year when I flew back to Canada after living in Japan for three months, it was the people, (or lack thereof). I wandered around for the first few days trying to figure out where everybody was. It was a little disconcerting, was everyone hiding? On vaction? The feeling went away.
This time, it was the silence. Living in Osaka is a constant barrage of noise, noise that never ceases, (especially with the windows open to let in the cool night air). As I went to sleep the first night in Canada, the lack of noise was very tangible, it was a palpable quiet. All I could hear was a whine in my ears.