You are in for a real adventure. I would not take back this experience for anything in the world.
However, I do have a few words of advice. You really should get a prescription for an upset stomach. The food is different than what we eat in the states, and even though you might think you will be able to handle it without any problems. It is better to be safe than sorry!
Also, be sure to bring small packets of laundry detergent. It was pretty expensive to get your clothes washed at the hotels we stayed in. So, you might want to wash your things up in a bath tub.
Finally, be sure to bring some nice clothes for going out to dinner. I did not expect to go out to nice restaurants, and I really regretted not bringing proper going out clothes. You can buy clothes when you are there, but keep in mind that if you are tall or heavy, it will be difficult to find things in your size.
Other than that, use your best judgment when packing. Like I said, the trip is amazing and you will have a great time. Just be sure to keep an open mind when going to a new and exotic country!