duplicateMovieClip จับเวลา countdown

for (i=1; i<=5; i++) {
 _root["orange"].duplicateMovieClip("orange"+i, _root.getNextHighestDepth());
 _root["worm"].duplicateMovieClip("worm"+i, _root.getNextHighestDepth());
}
stop();
timer = 30;
countdown = function () {
 timer--;
 if (timer == 0) {
 clearInterval(countdownInterval);
 gotoAndStop(2);
 }
};
countdownInterval = setInterval(countdown, 1000);