Thanks for asking in healthcaremagic forum I understand your concern, but you should have thought this earlier before indulging in unprotected intercourse. Anyways variations of a week on either side is normally found in many females, so please wait for the periods and mean while go for urine pregnancy test from morning urine sample at your home only. If positive please visit a gynaecologist without hesitation for medical termination of pregnancy and if negative enjoy. All the best.