You picked a high-demand flight that is often full and had no status to snag the seats that are reserved for those with status. Next time you take that flight your QF Gold status would be enough to get you a better seat. Window seats are usually not the first to go (aisle seats are more popular) so it is rather ironic that you did not manage to get one. Any AA flight out of DFW tends to be full of high-status pax.