What birth control pills are more effective? i took 2 tablets of postinor 2 at the same time, are there effects of that and will it be very effective?

It should work, but: Plan B, Postinor 2, and other brands of emergency contraceptive pills can alter the menstrual cycle for the cycle in which Plan B or Postinor 2 was taken, and sometimes the next month's cycle too. One should be sure to check a home pregnancy test about 3 weeks after sex, because emergency contraceptive pills work most of the time, but not all the time.