When to see the doctor?

So as a preface, in 2016 I had to miscarriages but got pregnant the first attempt for both of those, I got pregnant with my daughter later 2016 on the second attempt after a D&C.

Fast forward to this year, I got off BC end of April and started tracking with this and another app, probably started using ovulation strips in June. So may and June nothing happened, late July early August I had a cycle and had a positive pregnancy test aug 16 but that ended in a miscarriage late August. I was prescribed pro after one to start taking after I get a peak ovulation test since I had low progesterone during that mishap. September was a dud, and I’m due for my period in a couple days but I’m assuming it’s coming since I had a negative test today. My point is, when should I see the doctor about possible fertility issues? I’ve been told I have fibroids when I was pregnant with my daughter. I’m going to start checking my basal body temp this next cycle too to help keep track but I just don’t get how it was no problem conceiving in 2016 and this year is been almost a full 6 months with a miscarriage included