Can implantation bleeding last for 5 days and be heavy enough to fill pads on the second day of bleeding? the bleeding started on normal day as expected period. this was month 5 of being on birth control.idk if it was a shorter period or implantation

Doubt it: Sounds more like a menstrual period. A positive pregnancy test can tell a woman that PRIOR spotting was actually implantation spotting. It can be hard to tell if a woman is pregnant because some of the symptoms seen in early pregnancy can also happen in non-pregnant women. A urine pregnancy test gives a reliable result about 3 weeks after sex (3 weeks after when conception might have occurred).