"Cheryl's Birthday" Short Story

This is totally off topic for this blog but I wanted to share it anyway. I wrote this stupid (very) short story last night, inspired by a logic problem I saw online. Even with the solution it still took me 15 minutes to figure out. Apparently I'm not alone since a lot of people still find it confusing. The scenario in the question is also really odd, so it inspired me to write a situation in which a girl might be so coy about telling people her birthday. It's meant to be silly but also explain how to solve the puzzle. If you want to figure out the puzzle first, wait to read the story.

Cheryl's Birthday

    Two gigantic dorks walk into a high school classroom holding hands.
    “Where should we sit?” Says Dork 1.
    Dork 2 points out a girl wearing a “Bazinga!” shirt. “Let’s sit by her. She looks like as big a nerd as us.”
    They sit down on either side of the girl and ask her name.
    “Cheryl,” she says.
    “Hi Cheryl, I like your calculator, Cheryl. You’re my new best friend, Cheryl,” says Dork 1.”
    “No I’m not,” says Cheryl, scooting her desk away from him.
    “What’s your birthday, Cheryl?” Dork 2 breathes in her ear.
    “Um… Why?”
    “We want to give you a present.” Dork 1 winks.
    “No thanks,” says Cheryl.
    “Come on Cheryl, we really want to know your birthday.” Dork 2 leans in close.
    “Fine, if you can figure out my birthday with a stupid logic-puzzle, you can be my friends. But if you don’t get it, you have to leave me alone!”
    Cheryl writes down a bunch of dates and says, “I’ll tell one of you the month and one the day.”
    She whispers July in Dork 1’s ear, and the 16th in Dork 2’s.”
    Dork 1 knows that if she whispered the 18th or 19th, Dork 2 would know the answer because they appear once. But the day can’t be the 18th and 19th since they are not in July, so Dork 2 can’t know the answer because all the other numbers appear twice. “I don’t know when Cheryl’s birthday is, but I know that Bernard does not know too.” He says.
    Dork 2 knows that since Dork 1 knew that he couldn’t know the answer, May and June are out because they were the only months with a number that appears once. The only month left with a 16 is July, so the date is July 16th. He says “At first I don’t know when Cheryl’s birthday is, but I know now.”
    Since Dork 2 knows the answer, Dork 1 figures out that it can’t be July 14th because 14 appears twice. If it was 14, Dork 2 would still not know. “Then I also know when Cheryl’s birthday is,” he says.
    “Cool, we have a best friend now!”
    Cheryl gets up and says, “I changed my mind. I’m gonna sit somewhere else. You guys are way too nerdy.”
    Dork 1 looks at Dork 2 mournfully. “At least we know her birthday.”
    “Yeah.”