How did Jon Kraukauer feel on top of Mount Everest?

John Karkauer was numb when he finally reached the top of Mount Everest..... tired, cold, and unable to really enjoy his accomplishment.

I stood atop Mount Everest, gasping for air at the topmost limit of earth’s atmosphere. Standing on the top of the world, I cleared the ice from my oxygen mask, put my shoulder against the wind, and stared at the vast view of earth below. I understood on some dim level that it was a spectacular sight. I'd been dreaming about this moment for many months. But now that I was finally here, standing on the summit of Mount Everest, I just
didn’t have the energy to care.