The evidence from the text that gives you the impression that Kovaloff is intimidated by his nose is that he has to gather his courage before he is able to speak to the nose.
Explanation:
The lines "He began to cough discreetly near it, but the nose paid him not the least attention." show that he is not ready to speak directly to the nose at the beginning and later when he does he receives a very despective and arrogant answer from the nose, he also used very respectful word to refer to the nose "Honourable sir," said Kovaloff at last, plucking up courage, "honourable sir."
