"Throwback Thursday -- that time I had dental anesthesia...laughing gas + novocaine + Hamilton = you're welcome. #TBT @hamiltonmusical," she captioned the video of her speaking to someone on the phone while in the passenger seat of a vehicle.
"They did the sad part of Hamilton and I started crying. I couldn't stop," Garner exclaims to the person on the phone. "They said, 'Are you OK?' I said, 'It's so beautiful.'"
The mother of three then bursts into laughter. "It's so beautiful. Listen to this song," she continues mid-laugh. "So, I told them about it. They have to see it."
It's been less than a month since Garner joined Instagram and she's already got the hang of it. "I am officially on Instagram! So, please follow me because isn't that how this works...? Xx, Jen," her first caption read.