Dealing With The Negative Comments

As a child, I was always told by my mother things are appropriate and inappropriate to say to a pregnant woman so given I am currently 25 weeks pregnant with my first child, I always thought other people would show me the same courtesy. I have been told things about my body throughout this entire pregnancy that are possibly not meant to be hurtful but still are and some that are just downright rude. I've heard "wow are you sure you're only pregnant with one baby? There has to be two with how big you are" or "are you carrying triplets?" & my favorite "oh my daughter is due 3 weeks before you are and she's a lot smaller than you" among other lovely comments. I try to be tough and let the comments roll off my back but this is my first child and I feel really insecure. Any other mama's been through this?