Implantation?!

Savannah • Baby girl - Aliviah Mae 10.29.15 & Baby boy- Archer Neil 05.31.17 👨‍👩‍👧‍👦
Hey ladies! I'm supposed to get AF in 3 days but today I had just the tiniest amount of pink blood drops in my underwear. Last time we could've conceived was May 22nd so maybe it was implantation bleeding? I never had it with my first pregnancy. How long should I wait until I take a test? If anyone could comment their experience that would be great!