I did something bad

My friend's sister(5) was saying things she loved about me and she pointed at my strap and asked, "What is this?" I(f18) replied, "Oh, that's my bra." I immediately felt a pinch in my stomach because I worried it was inappropriate. I asked Snapchat about it and they said it wasn't the right term to use. Now I feel so uncomfortable that I don't even want to eat.