Blaming myself

I'm 13w2d pregnant now and terrified that I am going to do something to make this baby sick too. I am afraid to get connected to him because I'm afraid we will go to the high risk doctor for the 16 or 20 week scan and find out that this baby is sick too... I just want to know is it normal for me to keep blaming myself for what happened to my son? And be terrified to have the same happen to this baby too?? And be terrified that I am the reason? Especially since there was no identifiable cause genetically for what happened. They said it was developmental...