Fear of miscarriage

I'm currently pregnabt with my 2nd at 5weeks. I  having a severe fear of miscarriage or things like the baby not having a heartbeat when I get my ultrasound. I'm not sure why I'm feeling this way.
I never felt like this with my first, maybe because I wasn't trying with the first, it was an accident that happened as I was exiting a terrible relationship. This time I'm married and intentionally tried to get pregnant. 
Is this norman? Does anyone else have these fears?