He felt everything change as he regenerated; he should be used to it by now, but he wasn't. And then he was a new man, ready to take on the universe!
"Alright, new me!" he stretched. "New voice! Hello! ...sounds familiar. Must've run into this version of me before... Nice. Two legs, and I think this form's a keeper. Course, I can't really change now... Oh, yes, usual post-regeneration quirks to get out and all that. That'll be fun."
"Um...Doctor?" a small voice asked.
He turned. "How do I look?" he asked his companion. "Am I ginger? Please tell me I'm ginger. I've lost count of how many times I'm not ginger. It's ridiculous."
"Sorry, you're not ginger," she said, staring at him with an odd expression. "What happened to you? You're all... different."
"Regenerated, that's all. I was dying and to save myself, I changed every cell in my body. I tried to tell you, but you wouldn't shut up about getting aspirin, which, for the record, you are not allowed to give me. Ever. Under any circumstances."
She frowned. "This is too much... I've fought monsters and faced ghosts and all kinds of aliens; you can't go changing your face on me. I want to go home now."
He supposed he'd always known she'd leave. She'd never been as excited about the strangeness of the universe as he'd been. Often, while he'd been laughing, she'd started crying. Ah, he missed the old companions. What he wouldn't give to see Rose, Martha, Donna, or Amy again.
"Alright. Home it is," he said, throwing the lever.
"Thank you."
They stepped out of the TARDIS. She gave him a rather stiff hug. "Are you really the same person?" she asked, shaking her head. "Well, I guess it doesn't matter, now, does it?" And with that she was gone.
He watched her run into the house and hug her roommate, who waved confusedly to the Doctor. He smiled, then glanced at his reflection in the window.
No. He couldn't be. He wasn't... He ran back to the TARDIS, and into one of the bathrooms. He examined himself in the mirror. It was him, down to the last detail.
"No," he said, laughing. "No! All those times. And it was me! Figures. Oh!" he cursed under his breath. "That means I'll have to keep a stable time loop, which means... Oh, that's great. I get to be an idiot! How can I pull off that? I'm a genius and he was... not."
The newly-minted Doctor retreated to the wardrobe room, digging out some typical, early 21st century clothing. It didn't fit his taste at all, really. He wanted... What did he want? He perused through the racks of clothing, stopping at combat gear. That's what he wanted. It was a shame he wouldn't be able to pass off as a normal human if went running around in that all day.
He returned to the console room, sighing, "Well, old girl, it looks like I'm going to have to trust you to take me to where I need to be to keep the time line from going wrong. All up to you," he pressed a few buttons and the TARDIS took off.
He opened the door and stepped into 2003, Earth. He smiled to himself and walked across the street. He twirled around, looking up at the houses he'd once been quite familiar with. Someone bumped into him.
"Sorry, mate," the girl said.
It took him a minute to form a reply, "No, s'fine. I was just looking around... Do you know if anyone's renting nearby?"
"Um, Mrs. Johnson was looking at getting a lodger... Were you looking on your own, or were you going to share with a girlfriend or someone?"
"Nah, it's just me. How can I get in touch with her? This seems like a nice place."
"Yeah," she said sarcastically. "Yeah, it's a great. Once you get past the ways it looks. And the people. And the incredible lack of things happening. I mean, if you can live with all that, it's a brilliant place."
He laughed.
"Here," she fished around her pockets and came up with a scrap of paper and a pencil. She scribbled down two numbers on the paper. "That's her number; her name's is Alice... and that's my number, if you need someone to show you around or something. I'm Rose," she said, shaking his hand. "And you are?"
He hesitated before saying the name he'd be using for the next few years, "Mickey; Mickey Smith."
"Nice to meet you," she grinned.
"See you around," he said.
"Yeah," she turned and disappeared up a flight of stairs.
"Rose Tyler," he whispered under his breath.
He laughed, unnerved by what had just happened. He, the Doctor, would pass for a human and become a companion. Who knew what would happen. Well, he knew, of course. He'd be Mickey Smith, technological extraordinaire and 'tin dog' of the TARDIS. Of course, the TARDIS know who he was right away. To think she'd been hiding it from him all these years.
It dawned on him that this was 2003. For the next couple of years, he'd have to endure unimaginable horrors. He'd have to get a job, a place to live other than the TARDIS, and he'd have to pay rent.
Stupid stable time loop.