No Time to Waste

This is a continuation of my other story, The Timeturner and The TARDIS, which I wrote about 2 years ago. The Doctor returns to Hogwarts with a completely different face, a damaged TARDIS, and a mission to come back for little Amelia Pond. But there's an inevitable price that can't be rewritten, fixed in time. Can Hermione and the Doctor figure it out before it's too late?