Past perfect tense

I'll post just a little part of a book that I'm reading.
______

"Oh, please," said Meredith.
"And Matt-that boy is simply poetry in motion..."
"And neither of them is mine," Elena said flatly. Under Meredith's expert fingers, her hair was becoming a work of art, a soft mass of twisted gold. And the dress was all right; the iced-violet color brought out the violet in her eyes. But even to herself she looked pale and steely, not softly flushed with excitement but white and determined, like a very young soldier being sent to the front lines.
Standing on the football field yesterday when her name was announced as Homecoming Queen, there had been only one thought in her mind. He couldn't refuse to dance with her. If he came to the dance at all, he couldn't refuse the Homecoming Queen. And standing in front of the mirror now, she said it to herself again.

Did the writer use perfect past because he didn't consider the blue day the same way as the red one?
Is there any difference in using perfect past when writing a book and in "real life"? Writer almost always use it to distinguish times in the past, while we don't always use do that. Especially when the sequence of events is clear?
If he came to the dance at all, he couldn't refuse the Homecoming Queen. - Is this the second conditional and what does the sentence mean here?