Miscarriage

I am so sad. I was pregnant last year, and when i was on week 12 , ultrasound showed my baby was dead. I couldn’t believe when the doctor said: i am sorry, but i cant hear the baby’s heartbeat. My world broke down. After 4 months, here I am trying get pregnant. My period is irregular and late, but after loads of negative results tests, the sadness and emptiness came into my heart. I laying in bed the hole day, crying. I have a child she is 4 years old and she is the reason I’ve been trying to be alive. I go on therapy but its not working . Dont know what to do