How long after negative beta did you get period?

We got the horrible news on Friday that our FET failed. I stopped taking oral estrogen and stopped progesterone injections. I've kind of felt like my period has been coming for days but nothing yet....how long after stopping meds have others gotten your period? I need to start my period to schedule my hysteroscopy, so I wish I would just get it!! Our issue is low AMH. My uterine lining looked great and my doctor said "you should be pregnant right now". I just don't understand what went wrong. I had a large uterine polyp removed about a year ago, so the next step is another hysteroscopy to make sure there are no new polyps.