First period after chemical pregnancy?

On July 22nd I had my first beta following IVF # 2 and it confirmed I was pregnant. I started spotting that same day, and two days later I was told it was a chemical pregnancy. I know your cycles can be out of sorts after a chemical pregnancy, but it's been 40 days today, (6 weeks on Thursday) since I started miscarrying and I have yet to get a period. For the past week I have beeing PMSing, crampy, moody, and checking every 2 seconds to see if AF has arrived and nothing. I finally caved and tested, and BFN, which I assumed would be the case. It feels like I have my period, without the bleeding. I have that "heavy" feeling in my uterus, and very crampy. I know everyone is different, but can anyone tell me how many days it took them to get AF after a chemical PG? I'm going bonkers waiting!