My heart is breaking

I just need to vent. Our best friends had a baby and we’re so happy for them and I love seeing him but it breaks my heart. On Boxing Day my partners sister said she was pregnant and it hurt so bad as I had a miscarriage last Boxing Day. I’ve had no period for four months, blood results say I’m not pregnant. They won’t do hormonal testing till I’m six months late and I’m scared there will be something seriously wrong and I’ll never had a baby. We’ve been trying since August 2021, so I know not massively long. Has anyone had similar with their periods randomly stopping? I’m only 24 and not stressed. I’m not the skinniest but I’ve always had normal problems so doubt that’s anything to do with it.