BFN 😭😭

I'm so crushed. We used opk's this month & we had the timing down to what I thought was perfect, but I'm not pregnant. I just don't understand. I didn't think we would miss it. I've heard so many stories of girls I'm close with just going off their apps when the ovulate & only having sex like the day or 2 before & still ending up pregnant. I just always feel like why me. First my mmc in September & now still not conceiving. I'm so heartbroken 😭 I got my positive opk on 700am the 20th & also 530pm the 20th