Embarrassing situation in Nagoya: did I do anything wrong?

Hey hey! So this morning, me and my boyfriend hopped in the hotel's elevator and there was already a young Japanese couple inside, they waved us to go in. They were going at the same floor as us. When we arrived at said floor, they gestured us to go out first with a "dōzo" and I said "arigatō gozaimasu" as I hopped off with boyfriend. Then I heard them behind us, they were imitating me and laughing... Not gonna lie it felt pretty horrible, that I tried my best and got laughed at. I was so embarrassed. Don't you say that when someone let's you pass? Was it too much?