For international students, this is even more true. Experiencing sharp changes in values and communication patterns can cause stress.
Public transportation is different from back home.
No one knows where your country is located. The media offer sparse international news, and most of what you see is about local crime and corruption. Fortunately, what you will experience is not all negative and you will soon get your initial cross-cultural trauma in perspective. Of course, there will be some values that are hard to understand or accept. The population in the U.S. is highly mobile, pragmatic, and a melting pot of more than one hundred primary cultures.