Dormitación is a less common, more formal word for the act of sleeping or falling asleep. While dormir is the verb for "to sleep," dormitación emphasizes the process or state of being in slumber.
In the context of the song, the artist sings, "Esta cama siempre está vacía y hace difícil la dormitación" (This bed is always empty and makes dormitation difficult). This choice of word highlights a sense of loneliness and the struggle to find rest, making it more poignant than simply saying "makes it difficult to sleep."
"Documentales" is a quiet, melancholic song about feeling worn down and invisible. José Madero sings about an apathy so deep that even sleep becomes difficult, describing "unadmirable plans" he'd rather not name out loud.
The recurring line "no me harán documentales" ("they won't make documentaries about me") is the heart of the song: a feeling that his pain and his life will pass by unnoticed by the world. Rather than asking for help, the narrator just wants an ending that comes quietly, "sonriente" (smiling), instead of anything more public.
The closing "Enhorabuena, por fin lo lograste" ("Congratulations, you finally made it") lands as bitter irony rather than celebration, a line aimed at himself for finally arriving somewhere he'd been dreading.