Despite only reaching #51 on the Billboard Hot 100, the single was considered a strong fourth single from Lopez, charting inside the top 20 of several charts.
The track contains a sample of Strafe's song "Set It Off" (1984).
Lyrically, the song is about Lopez being in a good mood, with nothing bringing her down.
Lopez recorded her vocals for the song at Daddy's House Recording Studios and Sony Music Studios in New York City.
Describing "Feelin' So Good" as a "mid-tempo bop" and "sunny party song", Arielle Tschinkel of the website Idolator called Big Pun and Fat Joe "the peanut butter to Lopez's jelly. Smooth yet sweet and complete perfection together."