12 days late, bfps and bfns and negative blood test

Obviously I'm not pregnant from a blood test today I'm just so confused. I had 4 faint but definite positives on frer then now all negatives I went to get blood test today and that also was negative. So not only is my period being so late odd but 2 days after expect af I had 2 days of the lightest pink tinge only when I wiped(not even every time). I thought forsure implantation which I've never experienced with none of my other pregnancies. Im pretty intune with my body and have always called pregnancy before even getting a bfp, this time I'm just so confused. I know there's possibilities of chemical but I would think I'd start bleeding by now. Anyone had similar experience? I have no PMS symptoms either which I have always days prior to af and my cervix has been high since I started checking (about 2 weeks ago). I have an ob appt on feb 14th which was suppose to be prenatal check but they still want me to go in due to the lack of period and bfps/bfns