Hi. Kebiasaannya bila upt negative, any bleeding is considered as menses, unless upt dah +ve, then bila ada bleeding baru kita akan consider as implantation bleeding/threatened miscarriage. Bila Dr dh confirm it is not a threatened miscarriage on subsequent scanning, and bleeding tu dah stop, barulah kita panggil implantation bleeding..but u can try to repeat upt in a week to be sure. Good luck