Lagunas literally translates to "lagoons". However, in this song, it's used metaphorically to mean "gaps" or "blanks".
Peso Pluma sings about having "Lagunas en mis pensamientos" (Gaps in my thoughts), creating a powerful image of confusion and memory loss from the pain of a breakup. This poetic phrase shows how a simple word can be used to describe a deep emotional state, making it a very memorable part of the lyrics.
This song is a perfect example of trying to act tough after a breakup while you're actually falling apart. Peso Pluma and Iván Cornejo go back and forth between bragging and admitting their pain. One minute, they're all about moving on: "Fiesta, amigos y unas morras pa' salir" (Parties, friends, and some girls to go out with). They even claim, "Ya te borré de todos lados" (I already deleted you from everywhere), which is the ultimate modern breakup move.
But then, the mask slips. They confess the truth: "El tiempo pasa y no se pasa este dolor" (Time passes and this pain doesn't pass). The whole song is built around this idea that time has stopped since the relationship ended, with the line "No entiendo por qué el tic-tac del reloj paró" (I don't understand why the ticking of the clock stopped). It's a sad, honest look at heartbreak, where you tell everyone you're fine but at night you're just staring at your phone, sinking into depression.