Does American Airlines give credits if your airfare goes down like Airtran does? I booked me and my son's flight for our 3/14 trip, but am now needing to book my DH's too since he can now go. We booked ours for $363 RT and the current price for the same flight is $481. It's making me nervous to not have it booked yet, but don't want to over-pay. Thanks!