How to differeniate between implantation and menstrual bleeding especially if the bleeding came 5 days later than period, took levonorgestrel after the sex by 2 days. the bleeding was few on the 1st day &increased on 2nd &3rd day and lasted for 5 day?

About implantation..: Only after a positive pregnancy test can tell a woman that PRIOR spotting was actually implantation bleeding. It can be hard to tell if a woman is pregnant because some of the symptoms seen in early pregnancy can also happen in nonpregnant women. A urine pregnancy test gives a reliable result by 3 weeks after sex (3 weeks after when conception might have occurred) or 1 week after missing a period.