i found a a perfect text who describes my feelings.. it was on katarina's blog, who is also an exchange student. :

"A year has passed and now we stand on the brink, of returning to a world where we are surrounded by the paradox of everything and yet nothing being the same. In a couple of weeks we will reluctantly give our hugs and, fighting the tears,we will say goodbye to people who were once just names on a sheet of paper to return to people that we hugged and fought tears to say goodbye to before we ever left.

We will leave our best friends to return to our best friends.
We will go back to the places we came from, and go back to the same things we did last summer and every summer before.
We will come into town on that same familiar road, and even though it has been months, it will seem like only yesterday.
As you walk into your old bedroom, every emotion will pass through you as you reflect on the way your life has changed and the person you have become.
You suddenly realize that the things that were most important to you a year ago don't seem to matter so much anymore, and the things you hold highest now, no one at home will completely understand.
Who will you call first?
What will you do your first weekend home with your friends?
Where are you going to work?
Who will be at the party Saturday night?
What has everyone been up to in the past few months?
Who from school will you keep in touch with?
How long before you actually start missing people barging in without calling or knocking?
Then you start to realize how much things have changed, and you realize the hardest part of being an exchange student is balancing the two completely different worlds you now live in, trying desperately to hold on to everything.
all the while trying to figure out what you have to leave behind.
We now know the meaning of true friendship.
We know who we have kept in touch with over the past year and who we hold dearest to our hearts.
We've left our worlds to deal with the real world.
We've had our hearts broken, we've fallen in love.
There have been times when we've felt so helpless being hours away from home when we know our families or friends needed us the most, and there are times when we know we have made a difference.
Just weeks from now we will leave.
Just weeks from now we take down our pictures, and pack up our clothes.
No more going next door to do nothing for hours on end. We will leave our friends whose random e-mails and phone calls will bring us to laughter and tears this summer, and hopefully years to come.
We will take our memories and dreams and put them away for now, saving them for our return to this world.
Just weeks from now we will arrive.
Just weeks from now we will unpack our bags and have dinner with our families. We will drive over to our best friend's house and do nothing for hours on end.
We will return to the same friends whose random emails and phone calls have brought us to laughter and tears over the year.
We will unpack old dreams and memories that have been put away for the past year.
In just weeks we will dig deep inside to find the strength and conviction to adjust to change and still keep each other close.
And somehow, in some way, we will find our place between these two worlds.
In just weeks.
Are you ready?