+ OPK & recent miscarriage

So my last actual period was 08/25. I started bleeding 09/20 and assumed it was my period. I have been bleeding on/off since then. I found out I was indeed pregnant but at 6 weeks my hcg stopped doubling went from 655 on 10.02 to 833 on 10.4) and at 6.5 weeks ultrasound confirmed my pregnancy wasn’t progressing. I’m heartbroken as we were so excited to make my baby girl a big sister. Anyways, I think I finally stopped bleeding today so I took an opk to start tracking my cycles and it was VERY positive. Could it just be because of how recent the pregnancy was? How long did it take for y’all to get negative pregnancy tests/opks after a miscarriage? How long did it take to ovulate after a miscarriage? Sorry for the rambling, just going through a lot and would like some advice/opinions!! TIA ☺️