Ängie's debut album was supposed to be Everything Is Fake, with songs written back in 2016 and later, however, due to difficulties with production and promotion, she scrapped the project in 2018. In September 2019 she revealed the title and some songs she had confirmed to be on the album before were scrapped.
At the beginning of 2019, Ängie started working on a new project, that came to be Heartburn once Tail Whip came into the picture. The album took an entire year to be done because they got caught up in the production, and the songs were difficult to write due to their very personal subject matter. The album was originally going to have 12 songs but it was reduced to "the 10 best ones".
On her Instagram when she announced the lead single for the album, she stated "Its a new era, a new Ängie. This album is the most beautiful thing I ever created in my life I think. I hope you’re gonna love it as much as I do. We been working on it for an entire year!"
In an interview for Freak Fanzine in June 2020, Ängie stated that the album was still going to be released that year: "In addition to the Harrison album, I have another album that is ready and waiting. Hopefully it will be released after the summer. The albums are completely different from each other. Not Pushing Daisies is a bit more commercial and the second album is more artistic."
A month later, in an interview for Têtu, Ängie said why she decided to release two albums during the same year: "Because they are two very different albums! [...] Heartburn is a little more artsy, with sounds that are new to me. [...] It was more complicated for me to make, because it's not the music I usually make. In this album, each song represents a challenge!"
On October 12th, Ängie posted a photo with the word "Heartburn" in it and the lyrics to this song on the caption. It was the first time Ängie did a post on Instagram referencing the album itself and not its songs, which made fans believe it was closer to being released.
On December 19th, 2020, Ängie did an Instagram where she answered some questions about the album, talking about its cover and saying that she really needed to release the album because she knows how much the fans were "dying" for it. However, on the 20th, she posted a series of photos on her second Instagram account that were starting to form the album cover. She deleted the posts right away, but not before some fans printed them. She then posted a part of the cover on her official Instagram and when fans asked about it in the comments, she said the album was canceled. Then, she once again deleted all the comments where she said that, leaving fans confused as if the album was still going to be released.
On December 23rd, 2020, finally, Ängie posted the official tracklist of the album on her Instagram and announced that the album was coming on January 1st, 2021. She also started posting lyrics, previews, and background information about the songs in the album exclusively on her Patreon, until the release date.
In an Instagram live-stream on April 2020, Ängie said that the album was about her psychosis to love: "I think I have some kind of psychosis against loving people, because either I love them too much or I just don't know how to love at all".
"The album is mostly about my psychosis dreams, how I see love and how it's supposed to be, and how fucked up my mind is. So it's kind of the real Suicidal Since 1995, but completely honest" - said Ängie.
Tail Whip did an Instagram post about the album a day before its release and said: "For me Heartburn is an album about katharsis, it’s about the things we do to feel a little bit better even if the things we do are destructive. I think it’s a love letter to the past and what we once strived to be, but more like a “hey, I understand what you did, but it’s time for me to move on” - kinda thing. It’s a reevaluation of self and of persona. It’s about transformation through all these sad memories and stupid things we did or still do."
|1.||"Heartburn"||Ängie, Tail Whip||Tail Whip||1:43|
|2.||"Agnostic Dreams"||Ängie, Tail Whip||Tail Whip||3:57|
|3.||"Believer"||Ängie, Tail Whip||Tail Whip||3:27|
|4.||"Cherries and Whiskey"||Ängie, Tail Whip||Tail Whip||3:19|
|5.||"Dust"||Ängie, Tail Whip||Tail Whip||3:32|
|6.||"Namida"||Ängie, Tail Whip||Tail Whip||2:47|
|7.||"Low Life"||Ängie, Tail Whip||Tail Whip||2:55|
|8.||"Sad Sex"||Ängie, Tail Whip||Tail Whip||3:25|
|9.||"Numb"||Ängie, Tail Whip||Tail Whip||3:59|
|10.||"Psychosis"||Ängie, Tail Whip||Tail Whip||3:15|
- Ängie revealed the title of the album in the music video premiere of its first single Dust.
- During the listening party live-stream for Not Pushing Daisies, Ängie revealed that part of the album's delay was due to not getting along with the Tail Whip for a period of time.