questions ALOT and about "implantion bleeding!! help

Hey 👋🏼 everyone reading this , so i've been on the Dempo for four years since I had my daughter in 2012 I just recently stopped taking my birth control shot in September and the first my last injection was June 1 so I haven't had it since then and I was supposed to get it on September 1 and I haven't now I haven't gotten a period yet and I've been trying to conceive and at this moment I think I might have implantation bleeding?? because when I wipe the discharge is a little darker brownish redish isn't light kind of in between and I get regular paps and swabs and I just recently got results yesterday that I don't have nothing sexually transmitted or anything like that !!! Thank GOD, so back to the discharge,so the discharge was really milky thin white last week and then it just recently started to change color....my question is could it be implantation bleeding? And if it is....how long after would a positive pregnancy test come ? Or would it show positive now ? Please help 😏