"My Heart Is Calling" was written and produced solely by Babyface. It is a moderately paced R&B ballad, composed with "a beat". According to the sheet music published at Musicnotes.com by Sony/ATV Music Publishing, the song is written in the key of G major. The beat of the song is set in common time, and moves at a tempo of 104 beats per minute. It has the sequence of Em7–D/F♯–G–Am7 as its chord progression. Houston's vocals in the song span from the note of D3 to the high note of E5. According to Ted Cox, the author of the book Whitney Houston, the song sees Houston developing the low end of her range. Lyrically, "My Heart Is Calling" is a love song.
"My Heart Is Calling" garnered mostly positive reviews from music critics. Chris Willman of Entertainment Weekly viewed the song as a "dance-floor" ballad, while Elysa Gardner of Los Angeles Times noted that the song was influenced by both gospel music and funk genres. She also wrote that the song explores Houston's more soulful side. Larry Flick of Billboard magazine also noted the song has an "unusually saucy groove". According to Bob Waliszewski of Plugged In, "Houston exuberantly captures the joy of meeting a special someone" through the song.
Larry Flick of Billboard reviewed the song favorably, writing that it is "a wonderfully refreshing release that smartly side-steps her tried-and-true balladry in favor of a credible foray into jeep-funk territory." Steve Jones of USA Today wrote that "[the] Babyface-produced My Heart Is Calling; [...] have a spiritual feel. [They] help maintain a thematic cohesiveness that most soundtracks lack these days." Similarly, Elysa Gardner of Los Angeles Times also reviewed the song favorably, writing that "Houston shows her soulful side with equal panache, even if she has a tendency to overdo the obligatory vocal gymnastics at times."
"My Heart Is Calling" debuted at number 81 on the US Billboard Hot 100, issue dated July 5, 1997. Two weeks later, the song peaked at number 77 on the chart. The following week, it dropped out of the chart. On the R&B/Hip-Hop charts, the song debuted at number 43, on the week dated June 28, 1997. The following week, the song ascended to number 35, a position which became its peak.