Continuity mistake: When Ambrose, while standing with Elliott, admits to killing Alaya, in the first shot, Elliott is standing in front and to the right of Ambrose. In the second shot, he's standing to her left. (00:27:52)
Continuity mistake: When the Doctor stands between Restac and his fleeing companions, using his sonic screwdriver to disable the Silurians' weapons, as the camera angle changes, the Doctor's grip on the screwdriver switches back and forth between pointing it at the lizards and holding it straight up and down, รก la the Neuralizer from Men in Black. (00:30:30)
Continuity mistake: Near the end, when the Doctor is explaining to Amy that she will forget Rory when the crack in time is finished eating him because he's part of her personal timeline, and he has his hands on her temples, Amy's hair is covering her ears in some shots, but not others. (00:40:56)
Continuity mistake: When Amy is trying not to forget Rory, the memory of him getting shot does not show the laser blast striking him. (00:41:44)
Continuity mistake: When the Doctor takes the piece of TARDIS shrapnel out and looks at it, he's holding it differently between the close-up and the wide shot. (00:44:05)
Chosen answer: 1) When Stephen Moffat took over he ignored a lot of what had been developed before (there is not in-universe answer). 2) It would have killed Rose, so the Doctor absorbed the energy. His body regenerated before the energy could do a significant amount of damage that would prevent regeneration.