Try deep breathing or affirmative thoughts. Let your ob know your having alot of anxiety. Hydroxyzine is the anxiety med they put me on since my mind goes a hundred miles an hour all the time and I have anxiety about my anxiety lol. It's normal to be anxious but you don't have to suffer from it :)
once you get the heartbeat the chance of miscarriage is very low ,you should remind yourself that you have crossed that level so just keep your head up and be happy.
if you are stressed it passes to the baby and not good for both of you.
Just remember a happy soul means happy baby :)
Take each day as it comes, you cannot control what happens sometimes. I lived by this after already losing my first, it got me through my second 1st trimester. Am sure you will be fine and congratulations