What should i keep in mind when spending time with americans?

Next week i will leave my home country Sweden to travel to Africa as a exchange student. The accomodation where we will be staying is owned by a american university and there will be alot of americans there.

I have never meet americans before and i am a little nervous about spending so much time with them also my english speaking skills are something that i am insecure about.

I am worried that i will have a hard time with communicating and that this will lead to awkward situations, since i am not a supersocial person even by swedish standards.

Is there anything special that americans like to talk about that i should prepare answers for?