Really Sad

I have gotten this question more times than I can COUNT! And it does hurt tremedously!  Saying something hurtful to the person who said it to you doesn't really seem like a good idea.  The person didn't mean to hurt you, and just by responding to their question and saying, "I'm not", will make them feel like an a-hole, and that is all you need to do.  They will learn to not ask someone about a such a sensitive subject, unless they know FOR SURE! 
Also, about the clothes you are wearing.  I know that the shirts I have tried to wear that make me look pregnant, all have a seem under the bust, dividing the bust and the stomach.  They used to be called babydolls, and they can be called tunics as well.  These shirts make EVERYONE look like they are pregnant.  Also shirts that are too big add to the misunderstanding.  If this continues to happen to you, pay attention to what you are wearing when it happens.