If you could go back in time, what career advice would you give your younger self?
I would tell myself that when it comes to a career path, a lot of people are going to try to dictate what is right or wrong, good or bad. They will try to make your decisions for you. Not all of their advice will be good. Not everyone is actually trying to help.
Work is work, and life is life. There are many, many versions of success. Chasing any version but your own is a mistake, because you're the one who has to live it. Everyone else is just outside looking in.
There's a line in Fight Club about "working jobs we hate, to buy sh*t we don't need." Money is awesome, but be aware of exactly what you must do to get it. Working long hours, nights, weekends- being perpetually bound to routinely providing real-time email responses as midnight draws near will ensure that you won't get an opportunity to enjoy that money. Dignity may even erode. Relationships, too. To paraphrase Camus, you won't even know you're alive, because you're living like a dead man/woman. If years will pass before you take a real, go-somewhere vacation, you're doing it wrong. If you approach each day with a "let's just hunker down and get through this," you're doing it wrong.
That is the most honest answer I can provide.