I'm so sorry your going through this. I just had a chemical. My last PIO shot was Sunday and AF started yesterday, on Friday. It took about 5 days for me. I think the PIO goes out pretty quickly. As for when you can do the next cycle... I start BCP tomorrow, going right into the Next cycle no problem. Need to push forward and focus.
When I had m/c it took forever to get AF so I was surprised it came so fast this time. Also, apparently Chem is totally different, you don't have to skip a couple cycles. Tons of luck to you. (((((hugs)))))