why did the narrator Jerome repack everything

Dear Student.

When Jerome unstrapped the bag to pack the boots in, a “horrible idea” occurred to him. He wondered whether he had packed his toothbrush or not. He was a bit finicky about having his toothbrush packed every time he went on a trip. Jerome had to make a lot of effort to find his toothbrush. As he had packed everything, he had to rummage through the packed bag to find it. Jerome finally found the toothbrush inside a boot. Jerome had to reopen the packed bag twice owing to his forgetfulness. Once he had to reopen the bag as he had forgotten to pack the boots. The next time, he unpacked when he realized he had packed his tobacco-pouch in.

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