200 $ a day ? Thats about 6000 baht...
Does that include Hotel/Accommodation?
If not you will have a very good time with that kind of money (If you can bring more then by all means bring more, you will have an even better time
).
You will be arriving in high season, more crowds and more expensive, but still a lot cheaper than Europe or the USA, I don't know about Afghanistan prices....
Welcome to the board.