I'm repeating what others have essentially said, but ask yourself what's on your resume. If it says "Software Engineer" and that's all it talks about, then yea you might not find it's a lifetime career.

But if it's a diversity of things (that use or leverage software development) then you probably have a lifetime career ahead of you.

I've been writing software for over 40 years but I've never seen myself as having a software engineering career. I've been a research assistant in geophysics, a marine technician on research ships, a game developer, an advisor to the UN, and a lot more. Yes all through that I used software, but I did a lot of other things in the process of using it.