On the whole, you did a very nice job with this chapter.  I find Matt's bounciness endearing, though he played a rather small role in this chapter.  My only complaint is that I think you lost a little bit of Harry's character with: “No, not many would have done what you and your family did. I know plenty of people that would have cracked another one of my ribs and left me there. No one would take a stranger into their home.”  It just seemed unnecessarily angsty.  But you are the author.  

If you still need a beta reader, you can email me at annathecubsfan@gmail.com.  You can usually expect same day feedback from me.  I don't consider myself harsh, but I am critical, so be forewarned.

I think you've got a good start, I thought your descriptions of the wizarding world at war were very believeable.  However, I do think your need to be careful with your characterization of Harry and his impending romance with an original charcter (unless I'm assuming too much).  You've made Harry very independent and given him a grasp of magic that he never displays in the book, and then he's angry at Ginny on top of that when all she did in the book was try to avoid hurting him.  Combining that characterization with an American girl who has some sort of seer/prophetess power is a recipe for cliche if you are careless. 

All in all, though, I am curious to see where you are going.  Keep writing.