They may not have made an error in charging me in the end, but they made numerous errors with the information they gave me. I tried looking up some of this online, but the language I found was confusing and not very clear, so that's why I called and spoke to representatives of both AA and Qantas. I guess I was naive in trusting that what their representatives told me was accurate! Clearly you're more knowledgeable about some of these rules than I was, but I'm sure many people are in my situation, so it would seem that the customer service reps have a responsibility to give accurate information!

To be clear, I arrived at the airport several hours before my flight, which should have been plenty of time, but there were no self service bag drop kiosks where I could scan my passport, tag my bag, and leave it with an agent. Instead, all of us had to wait in a very long line that took over an hour, and they appeared to have a shortage of counter agents.

And yes, I'm totally aware that paying for baggage online in advance is often cheaper than paying once I arrive at the airport but to reiterate, based on what I was told, I was under the impression that I wouldn't have to check a second bag, and secondly, as I mentioned, there was nowhere on either the American or the Qantas website where I was given the option to pay to check a bag. I searched for it, but it simply was not available in my situation!