mid cycle spotting

I know this is an issue I should take up with my obgyn but I'm impatient. So since yesterday I've had some brownish pink discharge, which was light. Today I have the same issue but it's a little on the heavier side. Like not on my underwear but every time I wipe. This happened back in July and it turned out I was pregnant, but unfortunately that ended in a miscarriage. So my question is does implantation last this long and is the spotting normal?