Hello, Hilary,
Good revision! I'll also add that 'somehow' has grown on me. Still, there's an ambiguity in the 'it' in "Jack’s head / ached now in the light, but hadn’t it been / much brighter up there in the windswept house?" As in, does it refer to his head or to the general condition? One possible fix might to clear 'it' up might be:
Jack’s head
ached now in the light, but hadn’t it been
fine up in that brighter, windswept house?
I think it's almost there, Hilary!
Cheers,
...Alex