Unsure how to feel

Katherine
I've had 6 ultrasounds since I first found out I was pregnant, due to the fact that I got pregnant with an iud in. The iud was taken out almost a month ago, and in that ultrasound the baby and it's heartbeat...and a second sac that measured two weeks smaller. The ended the visit with an order for me to come back in two weeks to see another baby. Fast forward to Tuesday, they sac was still empty. At this point, I'm thrilled for the little gummy bear that they found that is growing, but I also feel guilty about the second baby that never developed. I can't help but feel like it's my fault because I never took a prenatal for those two weeks. I feel horrible for it, but I can't help feeling that I don't deserve to grieve because I still have a viable baby. I keep hoping that when I go back for my next ob appointment, the second sac will have a baby in it. Anyone else go through this?