chess online

In my attempt I played 2.) Nxf6+...Bxf6 3) Bxh7+...Kh8 4) Qh5...Ne2+ 5) Rxe2 at which point your site says this is not the correct move. I have not understood why. Can some one explain? Agreed black can save mate by replying 5) ...BxN and the if 6) Be4+ ...Bh6, but then I can play 7) BxB(b7) threatening black rook and lateron simply bringing the bishop back to e4.
godbole

Thanks, breakerofwind. It is now obvious to me also.
godbole