Glad to be off his feet, the Doctor closed his eyes for a moment and focused on the progress of his regeneration. There was still time to avert it. He'd have to siphon off the energy somehow, but he suspected, if the ship's medical facilities used some sort of regenerative technology, he could safely funnel the excess energy into them without having to change.
"Oh, I hate that term," he finally muttered in response to Galen's commentary on his physiology. "Did you ever stop to think that maybe your lot looks like something else that came first? Now if you'll excuse me, I really do have to pay attention to what I'm doing, or I'm likely to burn out your ship's medical systems if not all of your systems in general." He waved a hand in Donna and Amy's general direction. "Go on. Tell him about Time Lords. Nothing too terribly embarrassing though, all right? And if you start to see an energy spike in the readings, get inside the TARDIS and stay there until the regeneration is over. She'll make sure you're safe."
That said, the Doctor lapsed into what appeared, from the outside, to be a state of unconsciousness, but was in fact one of deep concentration. He needed to be careful if he was going to work with the ship's systems to properly repair the damage his body had already suffered.