smiling back, thinking something naughty and grinning, giving her a wink, those are all accepted things to flirt back with. You don't have to go straight for "are you flirting with me" lol
I'd probably deny it if asked too abruptly. I'd feel as if I'd offended someone and back paddle very quickly.
but that's me.
I'm not yelling at you RR. I'm just saying your brain talk is all about how vulnerable you were. maybe considering that she is too might help? that's all. She's giving a small chance she could be harassed by other people in the store after you leave, a small chance you could get angry, a small chance that you are taken and get snotty and reject her in an unpleasant way. the risks aren't all on one side... that's all I'm trying to point out to people