Why do i feel like this

Pls don't judge. I'm pregnant with baby number 3 it wasn't planned for. I have a 2 year old and a 1 year old. I always feel extremely upset that I'm pregnant i get soo tired I feel sick throughout the whole day and I literally cannot take the smell of most foods. My appetite is very low. I dont cook much for my husband.. this all makes me feel very useless. I have been crying every day sinse I got pregnant. The only thing that keeps me going is praying.