Earlier quoted context omitted.
Yes, I bet there were times that he did. Especially before he was "George Carlin, world famous comedian" and was just some guy trying to land enough gigs to feed himself.
Maybe. It's just as possible he always loved being a comedian, even when it was hard to find work. The point is that he found a job he loved. No one should live under the assumption that everyone hates their job because of a joke.
I am pretty damn sure there must have been days he would have hated his "job" as a comedian, because it didn't look like it was going anywhere. And remember, this was the era when fighter pilots and airforce people were considered the coolest ones, and he was kicked out before even completing his Air Force enlistment.
So, I guess it would be safe to say, he had doubts about himself, and he was trying to explore what he was meant to do. And I think we can agree, there must have been days when he hated his "job" as a comedian, but just HAD to keep going.
Just because you love your job, doesn't mean you are not going to hate/ don't care about it anytime in future. I don't think Love/Hate are mutually exclusive. At some point, there must be days when they occur intermittently.