culture shock.

Culture shock according to Wikipedia:

After some time , differences between the old and new culture become apparent and may create anxiety.That sense of excitement will eventually give way to new and unpleasant feelings of frustration and anger as you continue to have unfavorable encounters that strike you as strange, offensive, and unacceptable. These reactions [...] are typically centered on the formidable language barrier as well as stark differences in: public hygiene; traffic safety; the type and quality of the food. It's a very hard period for the people who need to adjust to a new culture, especially for those students who study abroad alone without families. In this period, people might feel that their lifestyle is totally influenced. Their biological clock is in a mess because of the time difference, they can't work well and can't rest well either.

I may have culture shock.