As Sandeul describes the composition of the single:
"Our title song, ‘BABY I’M SORRY’, is a song that Jinyoung hyung personally wrote, composed, and produced. It’s a song with a twist because it starts out at first with an intense trance rhythm with a drum beat base and then during the middle part, it changes to an exciting melody. After finishing the song, Jinyoung hyung let me listen to it first. I remember when I first heard it, the song was so good that hyung and I went to the studio that day and made a guide during the middle of the night. You will know if you listened to the song, but it’s a charming song where you’ll automatically sing along after only listening to it once. When you listen to the song’s unique points, you will probably find yourself singing along with the chorus. Saying ‘BABY I’M SORRY~’ too~ ^^"
trans. cr; hyejin @ b1a4trans | source cr; naver music | take out with full credits
Japanese lyrics were written by Inoue Tomonori (井上トモノリ). 
After mild success with This Time Is Over, Baby I'm Sorry was promoted for roughly two months through televised music shows. Additionally, the process of making the music video was featured in B1A4's first reality show, Sesame Player.
The music video features a more mature image promoted by the boy band. Their dark attire conveys each member's distraught and desperation to reunite with the female character featured within the music video.
On March 26, 2012, the song peaked at #18 on the Korean Billboard Charts.
The song was released as a B-side to their second Japanese single, Oyasumi Good Night.
- ↑ http://en.wikipedia.org/wiki/Oyasumi,_Good_Night
- ↑ http://b1a4trans.tumblr.com/post/19302572558/interview-navers-march-music-special-b1a4s-first
- ↑ http://mojim.com/tw110203x6.htm#2
- ↑ http://aviateb1a4.tumblr.com/post/19944755066/chart-billboard-korea-b1a4-baby-im-sorry