Had a similiar situation years ago
When I was in a TJ Maxx store in my town dressed casually, I wanted to try on a couple of things in the fitting rooms. I showed them to the attendant who waved me through with a number but as I was entering the fitting room hallway i passed another young woman who immediately read me and did a double take.
I went to the fitting room and tried on some jeans and such and the woman must of said something to the attendant about here" assumption" back there that was maybe a guy ( heaven forbid!!!!), because the attendant came down the hallway and yelled out " hello"? anyone in the back dressing rooms?",she obviously wanted to hear my voice to check out my gender for sure. When replying in my well rehearsed, well used female voice " Yes there is, in the back here", she did or said nothing more , even when I left. I had passed her test and convinced her so she must've thought the other young woman was nuts! :D lol!