Going crazy

Destany
Hello ladies, I'm so sorry for your loss.  I know how devastating it is to loose a baby. I had a chemical miscarriage at the beginning of July. 
Here's what I need help with, on June 23rd I got a BFP. On July 1st I started spotting with clots for 7 days.
My doctor told my that I would receive my AF on time. I was supposed to start July 17th and it still has not shown. I'm currently 18 days late, tested this morning and BFN. I'm having mild symptoms, my breasts feel like they're going to fall off! Any advice?