Cant enjoy new relationship due to repetitive thoughts about breaking up

I just recently started dating my best friend, yay! But I have been extremely anxious and hyper focused on the possibility of us breaking up. It’s keeping me from actually being able to enjoy this relationship. She’s my best friend and I don’t want to lose her. We’ve only been dating for about 2 weeks now, so very fresh relationship.

Does this feeling tend to die down after awhile? Is this normal???? I don’t know. I’m anxious all the time about this!!!!!