You’ll be fine. I’m in my 40s. My degree was in philosophy. I’m starting a job next week making six figures in accounting (a subject I’ve never studied). Most of us fall into things. Honestly the value of the degree isn’t so much the subject, but the determination involved in completing it. If you spend 4 years mastering a subject, you have a profitable skill. Don’t get me wrong, though, I floundered for about a decade. Pressed shirts, shoveled mulch, served food, etc. I found my footing in my early 30s and rode the wave. You can do this, too. You’ll be okay. It’ll be scary, but you’ll be okay. Follow your conscience and your instincts and you will be okay.