Sac in my vagina. Losing pregnancy

15w5d... Today, I went in for my regular blood work and pelvic exam just to find out my baby is basically falling out of me.. I lost my first pregnancy at 18w the exact same way. My cervix has completely shrunken so there is no way of saving baby. The most hurtful thing about it is the baby is completely healthy. Healthy HR of 154 and was bouncing for joy today during to ultrasound. I feel like a complete failure and a murderer. Now I’m just waiting on nature to take its course. Not sure if I will ever be mentally stable after this.