Perpetual Check Problem Here

Since your opponent played... The Damiano Defense
1. e4 e5 2. Nf3 f6?
You should have replied with a knight sacrifice on e5, b/c it is not really a sacrafice. If he takes it, he will need to give you a rook or be checkmated when you bring your queen out to h5 with check.
Very powerful and decisive opening for white.