Here we go again

So last month I got this app and we were thrilled cause it worked we tried for a month both taking prenatal and fertility support vitamins, I got pregnant and was surprised it happened but then I kept cramping like period cramps all day while at work and chills I went to my doctor and learned my hcg levels were falling and I was a pending miscarriage and 2 days later after hearing that it happened I miscarriaied at 5 weeks and 4 days I’m currently still bleeding like a heavy period and now here I am again husband was deviated and he too downloaded this app we are hopeful it will help us again become pregnant but that this is the rainbow baby we prayed for. Just a question for my ladies that have been through this do I mark this as a period to get my fertile window date? Or how can I tell I’m fertile again I never noticed ewcm before or egg white anything. I started bleeding Saturday it’s Monday now so when is the fertile window .