Stange Period/ Implantation??

Hi I am starting what I think must be an extremely early period, day 20 of a usual 27/28 day cycle. TMI but I woke this

What Causes Implantation Cramping?

For the Teen Who No Longer Wants a Period - The New York Times

When Does Implantation Occur? Symptoms, What to Expect

Germinal Stage CK-12 Foundation

What are the signs of successful implantation? - Quora

There's a chance, that your brown discharge doesn't have anything to do with your menstrual cycle.

What is Your Period Blood Telling You? - Natracare

Early signs of pregnancy that can tell if you are pregnant, even before a missed period

Symptoms of embryo implantation

/sites/default/files/pages/thumbna

Implantation Bleeding: All you need to know - Clearblue