Thank you for your question.
Yes you need o take emergency contraception. You can purchase this from pharmacy.
if you are sure you don't want to get pregnant for at least six months please consider using a more reliable method of contraception. Condoms are OK if you don't mind getting pregnant. The failure rate is almost 15%. Other methods like the oil have failure fate less than 1% are reversible with no long term effects and give you control over when you want a baby.
When using barrier contraception also be aware that there is no such thing as a safe period in young fertile women. Its all relative.
hope this helps