TTC post miscarriage (aren't we all 😩)

LJ
I had an early miscarriage on the 25th May, was only just over 4 weeks pregnant (so only just missed my period). I bled very heavily for a week having several flooding incidents then continued to bleed for 9 days. I went to the hospital and there was a clot/tissue around 2cm from the pregnancy stuck in my cervix, the doctor was able to remove it with forceps, on this day my HCG was 468 (halved in 48hours). A week after my HCG was 41. 
I know these questions have probably been asked before but has anyone ever been through similar when parts of the baby got stuck? 
Also when will I ovulate, do I count from the first day of miscarriage, from the time they removed stuff from my cervix (day 16) or from my HCG returning to 0 or when? 
When my HCG reaches 0 is that when I ovulate or is that when AF will start and a new cycle begin? 
Sorry for the questions!!