He perdido el norte is a fantastic Spanish idiom that literally translates to "I've lost the north."
Just like losing your sense of direction with a compass, it figuratively means to lose your way in life, to be disoriented, or to feel completely lost. In the song, the artist sings "He perdido el norte junto a ti" (I've lost my way with you), powerfully expressing the confusion and despair he feels after a loss.
This song from Spanish artist Iñigo Quintero is a spiral into obsession after a breakup. The singer feels completely stuck, repeating the same cycle of thoughts over and over: "Siempre lo mismo, siempre es lo mismo" (Always the same thing, it's always the same thing). He's lost all direction, telling his ex, "He perdido el norte junto a ti" (I've lost my way with you). It's a secret pain, too. He confesses, "No lo sabe nadie y es que me falta el aire" (Nobody knows it, but I can't breathe), which is such a dramatic way to describe the feeling of being trapped in your own head.
The world has literally lost its color for him—"He borrado los colores / Y ahora lo veo todo gris" (I've erased the colors / And now I see everything in gray). He feels like the other person doesn't truly know him if they haven't seen him in this state. The song ends with a desperate, repeated plea: "Porfa, no me mientas / Y menos a la cara" (Please, don't lie to me / And less so to my face), suggesting that on top of everything else, he's dealing with dishonesty, which makes the whole situation even more painful.