Temblor literally means "earthquake" or "tremor". It's a powerful word that creates a vivid image of shaking and instability.
In this song, Morat uses it as a metaphor for the intense emotional turmoil following a breakup. When he sings "Y ya pasó el temblor" (And the earthquake has passed), he's trying to convince himself that the chaotic, destructive phase of his heartbreak is finally over.
This song is all about the lies we tell ourselves after a breakup. The Colombian band Morat teams up with Jay Wheeler to sing about someone who is definitely not over his ex, but is trying his best to pretend he is. He calls it a "mecanismo de defensa" [defense mechanism] and admits he has a whole speech ready for when people ask about her. He repeats these lies so often that he starts to believe them himself: "Me lo dijo otra vez, hasta que me convencí" [I told myself again, until I convinced myself].
The whole chorus is a list of the things he tells himself to get by. He says he's better off, that she did him a favor, and that the "temblor" [earthquake] of the breakup has passed. But the saddest part is the admission that follows: "duele que aprendí a mentir / Para poder sobrevivir sin ti" [it hurts that I learned to lie / to be able to survive without you]. He's not just lying to his friends; he's lying to himself to cope with the pain. He even deleted all the photos and messages, but it's clear his feelings are still there.