The narrator runs away in terror until he can't run anymore. After a rest, he also finds that he's not terrified anymore – "My terror had fallen from me like a garment" (1.7.4). (And so did his hat – it fell off him just like a garment, probably because it is one.) What happened on the Horsell Common now seems like a dream to him.
He wanders home, noticing some ordinary things, like a train.
He stops to chat with a group of people who don't see what all the fuss is about, which annoys him.
If you're keeping track at home, you've noticed that in two pages the narrator has gone from a) terrified, to b) considering what he saw to be a dream, to c) being annoyed that people aren't taking the Martians seriously enough. The narrator himself points out that he's a man "of exceptional moods" (1.7.7), but we might say, "of exceptional mood swings."
The narrator arrives home and tells his wife about the Martians. She becomes very nervous.
Now, you might think that her reaction would make the narrator happy, since that's kind of what he wanted from the group of people he talked to on the way home. But no. Now all he wants to do is assure her that they're safe. To do so, the narrator points out that the Martians are weak and can't get out of the pit because Earth has a higher gravity than Mars.
Looking back on the invasion, the narrator tells us that he missed a few obvious points: 1) Earth air has more oxygen, which is invigorating (don't you feel invigorated?); and 2) the Martians are mechanical geniuses and can build machines to do the lifting for them. Bah.
But the narrator doesn't realize these things at the moment and enjoys his dinner, secure in the thought that the humans can kill the Martians whenever they want. He then compares himself to a dodo bird: "So some respectable dodo […] might have lorded it in his nest, and discussed the arrival of that shipful of pitiless sailors in want of animal food. 'We will peck them to death tomorrow, my dear'" (1.7.33). Now that's a nice cap to a chapter of extraordinary mood swings.