From the stands, Professor Quirrell tries to knock Harry off his broom with magic during the match, but Professor Snape’s countercurse stymies his efforts. Thinking Snape is the one trying to knock Harry off his broom, Hermione goes to distract him. Along the way, she really does stop the jinx when she knocks over Quirrell.
We left the story at the end of the last chapter on the evening of October 31, with the Gryffindors enjoying the remains of their Hallowe'en feast in the common room on the seventh floor. Now we move into the month of November. Just for the record, the first game of the season in Harry's third year was already in the first week of October. In the second, fifth, and sixth books, a Gryffindor match happens the first week of November. This will help us pinpoint the dates of the events in this chapter.
The next Friday in November is November 8, so that would be the earliest possible date for the start of this chapter. The Friday and Saturday after that would be November 15 and 16. Either set of days are possible. Since the first Gryffindor match has always been the first week of November in other years, we can safely assume that this Saturday is November 9.
Throughout the series, the reader pretty consistently sees things from Harry's point of view. The account of Harry's first Quidditch match is unusual because the perspective switches back and forth between Harry's experience participating in the match and what his friends in the audience are up to.
Hagrid states that "nothing [can] interfere with a broomstick except powerful Dark magic - no kid could do that to a Nimbus Two Thousand." In some ways this seems odd, but in other ways it makes sense. On the one hand, it seems strange that every broomstick produced would be shielded from powerful Dark magic. Is every rickety school broom protected from the Dark Arts? Nothing indicates that broomsticks are for some reason intrinsically impervious to most Dark magic. On the other hand, brooms are valuable, an important means of transportation, and dangerous in and of themselves. Having some sort of safeguard to limit the possibility for mishaps would make sense; perhaps Ministry regulation requires protection against powerful Dark magic as a safety standard. A related question stems from the second part of Hagrid's statement ("no kid could do that to a Nimbus Two Thousand."). Are Nimbus Two Thousands supposed to be particularly resistant to Dark magic? Are higher end broomsticks in general more protected from Dark magic than lower quality broomsticks? -BB
While everyone else is distracted by Harry and is bucking broomstick, Slytherin's Seeker, Marcus Flint, scores five goals. (These evidently counted, as they are part of Slytherin's final score at the end of the game.) This is an exemplary display of Slytherin cunning and resourcefulness.
Katie Bell is only a second year at this point. She couldn't have been on last year's team, so this is her very first match as well.
The Snitch Harry catches in this match is the one left to him by Albus Dumbledore in his will (DH7, DH34). Harry finally figures out that, because of how he caught it, he must put the Snitch to his lips to make use of its flesh memory.