Big 4 Manager in 3 Years

Hi all, I started in public accounting just a little over 2 years ago, made Senior at a big 4 last year, and have documentable evidence that unless I really screw something up I'll make manager this year, roughly 2 years and 10 months into my career, still at a big 4. I not posting this to brag, I like to think I work hard, but honestly a lot of the position I'm in has to do with a boatload of people between myself and the main partner leaving. I love the things that I've gotten to do because of my situation, 9 months ago I had really a basic Associate workload. Since then I've sold my first job, start to finish, basically manage 5 other Associates and Seniors, and am the main point to contact for 40+ clients. The flip side is that the stress is pretty heavy. Hours aren't as awful as they could be, but the stress is about like you might imagine for what I've decribed. My question is this: I'm pretty sure the light at the end of the tunnel is worth it, but once in a while the day to day the pressure makes me question it. I'd be indebted to know your thoughts. Thanks