I had the same experience too! One thing I learnt as I grew up was that, it doesn’t matter what people say to you. If you want to change how you look outside, start smiling everyday and practice is it so that you face becomes relaxed. I used to frown a lot and my mates in school used to pick on me. But eventually I’ve gone through all that shit and here I am happy with myself. Don’t worry about answering them, it can’t change anything. Also you can be cool by saying “It is what it is!”
Don’t get annoyed by people like that if you’re cool then! Be as you are. Time! It does wonders. Trust the process of being you.