I had a chemical pregnancy (first ever MC) happen to me November 4th. I was supposed to be 7-8 weeks nothing showed in my emergency vaginal and abdominal scan, nothing at all that would consider my pregnancy viable. My hcg levels dropped dramatically from 205 to 46 within two days. By three days a htp showed up unmistakenly bfn. I was cleared from etopic or anything else that could be wrong, my MC was the same flow and days as my normal periods except it was two weeks late.