Am I in the wrong for saying this?

afsu

So today a nosy coworker of mine asked me if I was pregnant. (I am 20 weeks pregnant btw) and I flat out said NO. I wasn’t expecting someone to ask me that question and plus I am not ready to announce it to my colleagues yet, haven’t even told my manager. I am now scared because how much longer will I be able to hide it! In a week or two it’ll start showing. Did I do anything wrong for saying No I am not pregnant?