Af or what? Brown discharge 4 days

So i thought i had implantation bleeding on the 19th. Woke up n wiped and it was bloody then nothing at all after that. Friday i had bad cramps and super light pink spotting so i put a tampon in and went about the day. Tmi but the tampon had brown on it. So i stopped putting in tampons and wore a liner since i coukdnt fill a tompon in 6 hours as usual. The liners have been black. Minimal, spotting like. When i wipe its pink but on the liner its brown/black. Could this be blood from implantaion? Today is day 4 of this spotting. Hasnt gotten any heavier.