Should I worry!!

Hellooo. So I had 2 periods in December. I started taking birth control on my last period which was December 23 I only took about 3 or 4 of the pills and stopped because I lost the pack. My period was suppose to start on the 17 and here it is the 22nd and still no period. Should I be worried?? Did I throw the balance off by taking those few pills??