Struggling

I am struggling with the first trimester. Physically and mentally. Mainly mentally. I need to just get to 12 weeks and then I’ll be able to breathe. I don’t know how to trust that I won’t have another mmc. Every single day is a battle despite seeing baby 3 times and everything looks wonderful. I’ve consistently measured 4 days behind on every ultrasound but it’s always had appropriate growth a week later. I’m just terrified my next one (whenever that will be) will cease to exist.