"I noticed it because the bottle was like a really nice aqua," she recalled.
It was early in the morning on July 3, and she says the glass bottle - corked with something inside - was right there on the sand.
She couldn't wait to tell her 14-year-old nephew Jack Smyth and 16-year-old niece Avery Smyth.
"We made a group chat," Jack said. "Everyone was decoding it and looking things up."
"She takes out a message in a bottle with a cork and it has the message in it and I'm like, 'Are you joking?'" said Avery.
Once Amy decided to open the bottle, she knew she wanted to document the process.
And since there were teenagers involved, they got to help put the videos on TikTok.
They recorded the uncorking process, which released a stench no one expected.
"As soon as we opened it my grandma's yelling, 'get it out of the house' because it smelled so bad," laughed Jack.
She also rolled on the painstaking removal of the note inside, along with the research that followed.
Amy is not a historical researcher, she's a greeting card designer from Haddon Heights, New Jersey.
But for the past several weeks she has gone through old newspapers, Ancestry.com and Reddit groups on old bottles -- all leading Amy to believe the bottle is from 1876.
The short note inside mentions a yacht based in Atlantic City called "The Neptune," along with a business card for W.G.&J. Klemm Gents' Furnishing Goods in Philadelphia.
"The outside of the bottle reads Barr and Brother Philadelphia," said Amy, hoping to learn more about the bottle and the company.
Steve Nagiewicz, of Stockton University, has spent decades diving into local shipwrecks and written books about underwater archaeology.
He says it's possible recent beach replenishment kicked the bottle up to shore.
"Getting bottles is always a treasured find and it's not that hard to do that. Especially for that time period where there were a lot of bottles made," said Nagiewicz.
Based on Amy's research, she thinks it could be the oldest message in a bottle ever found.
She's reached out to the Guinness Book of World Records and is waiting to hear back.
"I feel like the power of the old and the new, I mean the only reason I can do this is because of all the technology that we have," said Amy.
They hope to figure out who wrote the note inside, and hope social media might connect them to even more answers.
Anyone who wants to follow along can watch or contact Amy through her TikTok account, @asmythco
"It's just so cool to see all the research she's been doing and just see everything coming together and forming a full story," said Avery. "It's just so cool."