Complicándola is a gerund form of the verb complicar (to complicate), with the direct object pronoun la (it/her) attached. This structure is common in Spanish and interesting for learners.
In the song, the artist sings, "Así no quieras, siempre termino buscándola, Complicándola, quiero verte ya." He's admitting that even when he shouldn't, he ends up looking for her and, in doing so, "complicating things" or "complicating her situation" (or even "complicating her"). It perfectly captures the messy, on-again-off-again dynamic of the relationship described in the lyrics.
Have you ever had a few drinks and suddenly felt the urge to call someone you probably shouldn't? That's exactly what this song is about. Manuel Turizo sings about a cycle he can't seem to break. He says, "Vuelvo y caigo otra vez / Como cae la noche" (I fall again / Like the night falls), admitting this is a recurring problem for him. The trigger? Alcohol. He loses all his self-control, confessing, "Yo pierdo la autoridad con unas copas de más" (I lose control with a few extra drinks).
What happens next is a classic late-night phone call. He knows it's not a good idea and that they're not meant for a real relationship, stating bluntly, "para relación no nos da" (a relationship won't work for us). He's just calling because he wants to see her tonight. It's a super relatable story about giving in to temptation, even when you know you're just making things complicated for yourself and someone else.