I need help. My son is 2. He turned 2 on the 20th. I'm currently 26 weeks pregnant. And since the…

I need help. My son is 2. He turned 2 on the 20th. I'm currently 26 weeks pregnant. And since the day my son was born I have been having this overwhelming fear that something is going to happen to him. Like I'll go wake him from a nap or in the morning to get him ready for the day and he won't wake up... it's causing me to lose sleep and since becoming pregnant again it's gotten worse. I've talked to my Dr about it and they just said it's every parents fear it will pass.... please help I wake up bawling every night because of this