Hello,
I have gone through your query and understood the concern. If you had the intercourse during your safe period, there is no need for any emergency contraception because pregnancy cannot occur. However, if you had the intercourse during your fertile period, chances of conception are high and hence, emergency contraception is needed. You can either take the pill or go for the insertion of an IUD, depending on your need. It is true that emergency contraceptive pills create hormonal disturbances owing to their high hormone content. That is why their use should be restricted to the real emergencies, once or twice a year. Occasional use does less harm. Hope this helps.

Hello dear
Understand your concern
Yes you can use emergency contraception pill to prevent pregnancy the pregnancy. But you have to use with in 72 hour or as early as possible after sexual intercourse to prevent pregnancy effectively.
It is safe and it cause temporary disruption of menstrual cycle.
If you take
before ovulation: chance of withdrawal bleeding after 4-5 days will occcur.
AFTER ovulation: due to high progesterone prolongation of leutal phase and delayed in the menstruation by few days will occur.
Other side effects are: breast tenderness, tiredness, headache, dizziness, nausea/vomiting. But all these are tolerable and last for 4-6 days only.
So go for emergency contraception.
If emergency contraception pill will fail then still you terminate the pregnancy by using misoprostol and mifepristone under the advice and observation of gynecologist.(if period will delay and intrauterine pregnancy is confirmed by USG scan)
Hope this may help you
Best regards
Dr, Sagar