He didn't expect to wake up.
He woke up.
The first thing he saw was a faint glowing, and after a moment, he began to distinguish the shape of the TARDIS console—but his vision was still hazy, like he was looking through fogged glass. His thoughts, too, were scattered. He couldn't quite remember. All that he could really recall in detail were images and pieces of feelings—the delicate shell of a golden city shattering—screams, Time Lord and Dalek—and the violent burning of regeneration.
Those were the only things he knew, other than the fact that he should be dead. He couldn't fathom why he wasn't.
He had ended a war and two races and didn't he deserve to die for that?
Why?
Why?
Why?
He sat in the corner of the TARDIS, looking at the outline of the console, and then the regeneration sickness swelled up through him, and he choked quietly, and slipped into unconsciousness.
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When he awoke again he became aware of the silence.
He managed to make himself stand, to move to the console with his hands pressed against the cool metal, absently drawing his fingers over a few small buttons with no intent to press any of them. He floated in the darkness of space's endless night. Faraway, stars lit up the empty space, and somewhere out there, he knew that someone was drinking tea, or doing the dishes, or getting married, and their universe was small and manageable. For him, space was endless. Deep. Desperate. Scattered. And there he was, in the middle of it.
Alone.
The silence was overwhelming.
How many people had stood at this console with him, had befriended him and flown with him and seen the sky with him—how many times had he picked up strays that became invaluable? Where were they now? Where were they when things were crumbling?
He felt a brief tinge of bitterness and reminded himself that this was no one's fault but his own.
The TARDIS hummed like it was alive—as it was, sometimes, on the right day. It wasn't enough, but it was something, and for a moment he clung onto that, onto that quiet sound.
"It's just you and me." He murmured, and moved away from the console. He looked up at the ceiling, then towards the door, and through it out the windows into a starry sky.
He laughed. It wasn't a happy laugh.
"What now?"
########
He slept for a long time. He never looked in a mirror; he didn't want to see his new face. He slept until he couldn't sleep any longer, and then he ran up and down the halls of the TARDIS to make himself tired, and then he slept some more, cycles and cycles of this becoming his entire existence. He didn't like his dreams but he liked being awake even less. His dreams were infinite and terrifying, scattered with dark spirits and voices of people he'd killed and the sound of the city's shell shattering. And always, always, in waking and in sleeping, the same question returned to him.
How do I go on?
How could he? Now that he was alone and so, so guilty. How could he allow himself to go on? He considered killing himself, with a sort of far-away studied air. But no, something about that seemed wrong—living, it seemed, as he ran up and down the TARDIS hallways with only his footsteps and the inhale-exhale-inhale-exhale sound of his breaths for company, was his punishment. Someone, somewhere, someone who moved the chess pieces of life, had decided to make him live. So he would live. In this hell. He would go on, though he couldn't fathom how.
"I deserve to die." He whispered aloud one night, as he lay awake in his bed, drenched in sweat from his running, his two heartbeats pounding against his chest like they were trying to break free.
He ran. He slept. He ran. He slept. And he ran.
########
He had stopped running and sleeping. It was doing him no good. The pain was still there, ever-present, and the dreams were becoming worse and worse. Something had to change. He didn't know what. He didn't know if he had the strength, even if he could find what it was that he needed to do.
He stood by the console. He hadn't operated the TARDIS since Gallifrey fell. As he pressed his hands to the edge of the console again, he felt a slight shudder.
"So you're awake today, eh, old girl?" He murmured, and the TARDIS hummed louder in reply. He sighed.
Slowly, he walked across the floor, down the stairs to the door, and looked out the window. Outside, the stars were glistening like someone had poked holes in a dark sheet and was shining a flashlight through them.
"It's a big universe out there, isn't it?" He said to the TARDIS.
The universe felt bigger than before, now that Gallifrey was gone. He was anchorless. He was floating.
Some piece of the TARDIS's machinery made a whirring noise, as if reminding him that it was still here, offering a home. He laughed quietly and walked back over to the console.
"I don't deserve to be alive, you know." He breathed. "I deserve to be dead. I don't deserve any more chances, or whatever the universe is trying to give me. I should have died when the doomsday device detonated. I don't deserve to be here."
He breathed in, shuddering, shivering within the leather jacket he had picked out the night before from his closet after realizing the clothes from his previous incarnation were falling to shreds.
He felt very small, and, somehow, at the same time, like a giant.
For the first time in what seemed like an age, he set his hands to work at the console.
He began slowly, pressing one button, then the next, like a child only learning the controls. And then he began to move faster, faster, initiating the sequences he had memorized so long ago. Press, then press, twist that knob, pull that lever, press, that was it, settling in, press, press—and then, slowly, he stopped, realizing that he was done, that he was ready to leave—and the TARDIS was humming so loudly that in his ears, now so unaccustomed to sound, the noise became a scream.
He had to input the date. That was it. Then he would go. He would move away from this indeterminate, unimportant piece of space. To other things. To what?
Where would he go?
He hesitated here. He looked at the dials. His mind blanked. He felt empty.
And then he closed his eyes and breathed in and felt very sad and pressed his hands gingerly against the glass of the TARDIS, his TARDIS, which was now his only home.
"Take me where I need to go." He breathed quietly, and the TARDIS began to fly.