Rashi on the Prophets and Writings

the king’s sleep was disturbed It was a miracle. And some say that he took to heart that Esther had invited Haman; perhaps she had set her eyes upon him, and he would assassinate him.
to bring the book of the records It is customary for kings that when their sleep is disturbed, parables and lectures are recited to them until their sleep is restored. Our Rabbis, however, explained that since he took to heart [the matter of] Haman and Esther, he said [to himself], “It is impossible that none of my friends should know their plan and divulge it to me.” He [thought] again and said [to himself], “Perhaps someone did me a favor, and I did not reward him and they don’t care about me anymore.” Therefore, “he ordered to bring the book of the records.”

And let the raiment and the horse But he did not mention the crown, for he saw that the king became jealous because he said that they should place the crown on a person’s head.

And Mordecai returned to his sackcloth and to his fasting.
mourning and with his head covered Our Sages explained the matter in Tractate Megillah (ad loc.).

before whom you have begun to fall, etc. She said, “This nation has been compared to the stars and to the dust. When they descend, they descend to the dust, and when they ascend, they ascend to the sky and the stars.”