Well, I don't have this one figured out, but I do have lots of experience struggling with it.
Here is what I do when I get really anxious (like lately, when I am spotting): I pray in the car. (While DS is asleep in the back, because I am better at praying out loud.) I'm not all that theistic, either, but it helps me enormously to just say hey god-or-goddess-or-whoever, please help me keep breathing, and walk with me through my fear. And then I might go ahead and pray for peace, or for all the people in the world struggling so much harder than I am, and that turns my focus out of myself and keeps me connected with the world.
I had all the regular tests last time, and I'm skipping them all this time. Maybe I trust more. But I think mostly I know more--that the tests didn't make me feel safer, really, and the drawbacks of them.
I also am trying to replace the images in my head--or the talk in my head. Like when I hear myself saying what if I have a mc, or imagning that, I tell myself about all the friends I can rely on if that happens, and then gently refocus on something that's about love, not fear--like loving my son who's already here, and remembering his birth; or how excited I am to be working with a midwife this time and planning a home birth; or planning what really healthy yummy food I'm going to eat as soon as I can make it to the kitchen.
I don't know about fear drawing bad things to you--I have always been fearful, and have had a wonderful life. I keep telling myself, fear is just fear. It's scary, but it doesn't mean anything except that I'm afraid, and I don't have to let it run my life--I can just keep breathing and wait for it to pass.