Failed FET - When will I start to bleed?

Hello everyone,
I'm receiving <a href="">fertility treatment</a> and had a positive test after my first frozen embryo transfer. It's been such a hard and painful way so far and my husband and I were so happy and hopeful. My hCG was low from the very start though. Only 39, after 48h only 60. And after 4 days it had dropped to 14... I'm 5 weeks now. 
My doctor asked me to stop taking the medication on Tuesday and now I wonder when the bleeding will start? I had - amongst other meds - 4 pessaries + 1 injection of progesterone daily to suppress bleeding. When shall I expect the bleeding?
This is all so hard to handle. A whole new level of sadness. I can't stand to wait for the physical proof of losing our 2 little ones...
Thanks for reading.