TMI - implantation?

Alyssa • 29, wife, mama to our baby girl🎀, & baby boy💙
TMI - tues and wed i had mild cramping. Yesterday i had some pink/brown stretchy CM for about an hour then nothing. Today no cramping but just wiped and had some of this! .. tested this morning but neg. i have NEVER experienced this before. AF is due in exactly a week and she is never early!! Implantation? When is the soonest i can get an accurate test? Ahhhh im so hopeful🙏🏼