Rooms to spare: lucky or an error?

Oddly enough, it seems that I goofed up and forgot to reserve. I seem to remember calling, and booking with my husband's credit card, but neither of us seem to be able to find the confirmation number. I called the hotel, gave both of our names, and neither showed a reservation (though they wanted the spelling and not the CC#, and both of our names are easily misspelled).

Amazingly enough, I was able to book a reservation today (for the 26th-30th, not staying as long as others) at the Westin. I'm not entirely sure I even believe the confirmation email at this point. So, perhaps, there's still rooms available for odd times?

I guess I'm just confused all around! And very very lucky (I hope). Is there another way for me to check (to be sure we don't have two reservations now) against the CC#, and for that matter, if the one I just booked is legit?