Hi, your pregnancy depends on the time of your ovulation. Ideally for a normal cycle of 28 days, the ovulation would occur somewhere around 14th day. Let me stress this is not the thumb rule, it is generally around this day in a normal cycle of 28 days. The confirmation can only be done by noting the daily morning body temperature and different tests. So, in a normal 28 days cycle, if we assume that the lady ovulated on 14th day, then 12th to 17th day are the fertile period wherein there are chances of conceiving. Rest are termed as safe periods. In your case, 8th day seem to be unlikely but nothing can be said for sure as the life span of sperms are two days, so if you happen to ovulate on 10th day then there could be a possibility of you conceiving. So everything depends on your day of ovulation. Hope this answers your query. Thank you and take very good care of yourself.