Even though Ellison was happy about winning the National Book Award in 1953 for Invisible Man, he felt a little trepidation, too. (Hey, even masters feel self-conscious, just like the rest of us.) He felt his work was an "attempt at a major novel" and even said so in his acceptance speech. He talks about this and other things in this 1955 interview from The Paris Review.
"If the Negro, or any other writer, is going to do what is expected of him, he's lost the battle before he takes the field. I suspect that all the agony that goes into writing is borne precisely because the writer longs for acceptance—but it must be acceptance on his own terms."