I got my nexplanon taken out on the last day of my period in July. I take Metformin 3x a day and my period is always very regular, give or take a few days it always comes every month around the same time. I am a week late for my period but all tests I have taken has been a BFN. I'm to the point I have line eyes. I took a test earlier and tried to tweak it myself and part of me sees a faint line and, the other part of me says I don't see anything. Just confused why my period is so late?