Will you age out of teaching?

I’m in my mid 20s and absolutely love teaching, especially the kids. It’s my dream career and I’m willing to take pay cuts and deal with all the bullshit for the joy it brings me. However, I’m not confident I will be able to do it forever, or even well into my 50s. I’m getting tired already. What do you think? How do you prevent burnout? I just don’t see the light at the end of the tunnel if I have to do this for 30 years to get a pension.