Justin Bieber Twitter followers have been eagerly waiting for the upcoming release of 'Baby' singer's new single "Heartbreaker," and Justin Bieber teased his fans on Twitter by saying how much he's been working on his music!

Justin Bieber, who was rumored to have split with Selena Gomez recently, has failed to mention his girlfriend on Twitter for the past week. While Selena Gomez has been promoting her upcoming album, "Stars Dance" with new singles like "Come and Get It" and "Slow Down," Justin Bieber has been busy with his own new single.

Justin Bieber Twitter updates for the last two days have been "Really focused on this music. #musicjournals #heartbreaker #newsongs" and "Wrote another great song last night. Focused"

Justin Bieber first announced the news about his new single "Heartbreaker" a week ago by posting images of the album cover on his Instagram account. Bieber later posted updates on Twitter about the progress of his new music, saying "going to tell my truth thru music" on June 5.

In a Twitter post just five days ago, Justin Bieber wrote, "studio, music, friends, sunshine. life is good." and also "we work hard." Bieber has been kept his on and off relationship with Selena Gomez low key recently, despite their reunion earlier last month at Billboard Music Awards.

Judging from Justin Bieber's Twitter posts, the 19-year-old singer seems to be more focused on music than on his own love life, leading fans to speculate that Justin Bieber and Selena Gomez really have broken up.

Selena Gomez seems to be doing the same, as she is busy with the promotion of her upcoming album and concert tour, and she also expressed that she would like to be more "focused" on acting in her latest film projects, including "Getaway," which will hit theaters this summer.