Feeling very angry!

So we are supposed to be getting married 2/24/18. Everything is done, venue, band, flowers, my size 2 gown everything's done!!! A big beautiful black tie event that now we have to push back bc I'm due 3/10/17. I've had a miscarriage and was told I would not be able to get pregnant on my own so I know I should be over the moon. It's very selfish but it's reality and I'm pissed that everything now has to change. I don't know why I'm having such a hard time trying to be happy. My fiancé is thrilled but then he also thought we could still have the wedding and reception with me being 9 months pregnant, idiot! I just needed to vent bc now I'm going to our beach house with friends and I know I will not be able to partake in the events everyone will be doing. I just want my hormones to switch to happy and excited rather than angry and sad.