I don't know what to do

I can't cope, I had a mmc at 8+3 with my beautiful twins last month, I fell pregnant this month and having a chemical. This is not fair! I have two amazing children who I adore but I desperately want to do add to our family. People say "you have two that's more than enough, you don't need to be greedy" how on earth is it greedy that I want more? My son is 5 my daughter is 15 months and my son is totally amazing with my girl. I just want a baby !! I want to scream and shout from furstration. I'm supposed to be 14 weeks pregnant instead I'm not, I'm empty trying to stop my heart from aching :(