Getting Married… and My Brain Won’t Stop Overthinking

I’m at that age where marriage and having kids are starting to feel like real possibilities. I do want a family someday, but then my overthinking kicks in and starts creating every possible worst-case scenario about marriage and my future partner. I know marriage is a big responsibility, but I also know I’m probably thinking about it way more than I need to.
For those of you who are married, did you have these thoughts before getting married too? Or did you just take the leap and figure things out along the way?