Your living will only comes into action once you no longer can communicate. Whilst you are able to talk you should be able to declare your wishes or even change them. If however you slip into a coma without expressing these changes to another person in the company of witnesses, your original wills instructions will be followed.
Should a medical disaster strike you down away from home, you will be handled in the way the laws of your host country depict life support. Your living will may not be followed in some respects, but should you be repatriated the will comes into play again.
A living will is not a decision that should be left until you are not able to do it anymore. If you wish, get online support and forms to help you write a living will today.