I want a career change at thirty but feel like I'm too late

I've been in the same field since college and I'm miserable, but starting over at thirty feels reckless. Everyone my age seems settled while I'm googling 'how to become a ___ at 30' at midnight. I worry about money, about being entry-level again, about explaining the gap in interviews. Part of me thinks I should just be grateful for what I have. Part of me knows I'll regret not trying. If you changed careers as an adult, was the fear worse than the actual leap?