hi, i pill if taken within 72 hours after intercourse it will protection, as you taken within 2 hours it will give protection most probably, but it is having 1% failure rate, so chances of pregnancy cannot be completely excluded, as you had intercourse nearer to your expected date of periods, and as ovulation generally will not occur on those days, chance of fertilization is less, but frequent taking of pills can affect menstrual cycles, so better to shift to regular method of contraception. take care.