No reason to panic yet, overall luggage rarely disappears completely.
Have you tracked it yet?
http://www4.thy.com/baggage/start.tk?lang=e
As with all airlines, you will be
allowed to buy some essential personal items and some clothes and then charge it to TK. In the unlikely event it is completely lost normal compensation rules apply. Details are here:
http://www.turkishairlines.com/en-in.../baggege-delay
Your travel insurance will cover any value in excess of the airline compensation should the baggage be completely lost.