Do your best to be a bit more resolute. Everyone is anxious in life about something.
I can tell you for a fact there is someone your age or younger with a family and mortgage and a career change to think about. There’s probably someone your exact age whose entire career got derailed for any number of factors, wondering if they’ll get another go at it. But here you are wondering if your brain will stop working in a few years, or if you will ever get to write a movie.
You can write your movie right now. It’ll suck, but so what? Write another one. You’ll bomb all your upcoming interviews. Go to more.
From the immortal bard Arnold Schwarzenegger:
“Stop whining”.