"The only reason I'm deficient in salt, doctor, is because I'm so good at absorbing it." The alien's words echoed in your mind as you watched the Doctor pilot the TARDIS. Normally vibrant, he now looked distressed and in pain, though he masked it with his usual charming smile. His movements were unsteady; he walked with a slight stagger, his legs occasionally giving out, and the familiar glitter in his eyes had dimmed.

You grew more anxious with each passing day. He hadn't been eating, drinking, or sleeping, and it showed. His tie was rarely tied correctly, his jacket hung open, his hair was a disheveled mess, and his skin had taken on a sickly tone. The signs of his deteriorating condition were clear.

One night, unable to stand it any longer, you approached him. He was hunched over the TARDIS console, muttering under his breath, sweat dripping from his brow onto his pale, bony hands. His knuckles were white from gripping the console so tightly.

"Doctor," you called softly. "You need to rest. You're not well."

He glanced at you, and for a moment, his mask slipped, revealing the depth of his exhaustion and pain. "I'm fine," he insisted, voice strained. "Just a rough patch."