Why does the narrator hide the fishing rod from Sheila?

In the story “The Bass, the River, and Sheila Mant,” the narrator has a crush on his beautiful neighbor, Sheila Mant. The narrator is fourteen years old, while Sheila is seventeen. He spends a lot of his time trying to catch Sheila’s attention. For instance, he does “endless laps between his house and the Vermont shore so that she can notice the beauty of his flutter kick, or the power of his crawl.” Finally, he works up the courage to ask her out on a date, and she accepts. Instead of going by car, he offers to take her by canoe, hoping that she'll find this thrilling. He cleans up the canoe in readiness for his date with Sheila and even “polishes it with Brilo.” He leaves early and automatically carries his fishing rod with him. He also “ties on a Rapala plug, and lets it down into the water, with some line,” all because of his love for fishing.
Unfortunately, Sheila isn’t into canoeing or even fishing; when he picks her at her dock, she wears a “dubious expression” and asks him whether she can get her father’s car. He is forced to lie to her, saying that the canoe is a faster means of traveling to Dixford than a car. Even then, she gets in “reluctantly.” She does not even take up the extra paddle that is lying on the bow of the canoe. She then lets on that she hates fishing: “I think fishing’s dumb. I mean, it’s boring and all. Definitely dumb.” Since the narrator is especially keen on winning Sheila’s heart, he does not want to do anything that breaks the moment’s spell. As he says it, “He would have given anything not to appear dumb in Sheila’s severe and unforgiving eyes.” Therefore, his first reaction is to hide his fishing rod from Sheila: “He gently leaned forward, and slowly pushed the rod back through his legs toward the stern where it would be less conspicuous.” However, the rod catches a fish, and he is forced to lose this particular fish, out of fear of losing Sheila’s favor. Worse still, after the dance at Dixford, he ends up losing Sheila’s affection, as she chooses to travel back home in Eric Caswell’s car.