I like this.
I've never read an HP fanfic with this basis. That I can recall, at least. I've read a ton of them, so I can't really remember them all.
You see too have a problem with a space after an I. You end up with Iwas, Ihave, and so on.
Its just a typing quirk, yeah, alot of people have'em. I have a problem with periods. I always end up hitting the comma button, or the period button and the comma button. So I've made a habit of watching out for that and fixing it.
Aside from that, I can't see any errors as far as grammar/spelling.
Lookin' forward to the next chapter!