I welcome any reason to reflect on "I'm So Tired" - my favorite song by The Beatles - even if that reason is the scourge of restless sleep. When the body is weary but the mind still sharp and active, it's the ideal moment to share in John's comic exasperation with being unable to shut down for the night.
What I enjoy most about the song is John's vocal, so rich in tonal shifts, so full of humor, frustration, and wild-eyed conviction, and so indicative of the singer's messy, complicated nature.
John comes out of the gate as languid and defeated as you might expect. "I'm so tired / I haven't slept a wink / I'm so-ooo tired / My mind is on the blink / I wonder should I get up and fix myself a drink / No-no-no-oh." He couldn't sound any more drained of life, underscoring the toll of his inability to sleep but also the cruel, nagging humor of it (Note that, when he wrote the song, he couldn't do drugs because he was in India at a Transcendental Mediation camp). He continues: "I'm so tired / I don't know what to do / I'm so-oo-oh tired / My mind is set on you." The "you" is Yoko, and the mere thought of her instills John with vigor. From there to the end of the chorus ("You know I'd give you everything I got for a little peace of mind"), he sings as a man renewed, though in reality it's the anxiety of being separated from Yoko that sets him ablaze. He could suffer this bout of insomnia if only his future wife was at his side. Without her, he's pushed to the edge of madness ("I'm goin' insane"). At the start of the next verse, he retreats from it, but only briefly. He soon finds himself again overcome by vexation ("I'm feelin' so upset"), which spills into a miniature comic tirade against Sir Walter Raleigh, the "stupid git" who popularized tobacco use in England. Then another chorus and various repetitions follow, sung in the same vein.
A perfect song.
"I'm So Tired" is the sound of John's oversize personality working its charm. It's the sound of John stricken not only with the inability to sleep but, more so, the human condition. It's the sound of John laughing, crying, hating, and loving all at once.