I'm sorry you're dealing with the anxiety. I think it's completely normal. For many of us, having a loss makes it nearly impossible to have a completely blissful pregnancy experience, so you definitely aren't alone. I had to internally coach myself to physically relax, and I would do that by telling myself to relax one body part at a time ( "Relax your neck" "Unclench your jaw" "Take a deep breath"). If you feel like it's beyond your control, definitely not to you OB/MW. Make sure that your medical team is supportive of you and your fears. There is nothing worse than calling to ask a question about a concern only to be made to feel like you're an awful, terrible person or a huge inconvenience.
Good luck, momma. Every pregnancy is different. My loss group used to have this mantra "Today I am pregnant, and I love my baby."