Firstly, I'm so sorry you feel this way. As women in this society, we are constantly told we should look a certain way to be appealing - in the media, in ads, on TV and so on. And it can be so hard to deal with that. I personally struggled with my eating at one stage in my life, and felt the constant need to continue losing weight even when underweight, because I was not body confident. A huge part of my recovery from this was recognising this as a widespread issue and looking at all the forces at work, e.g. societal expectations. One way I did this was reading about and following women who promote body positivity, and removing people in my life who don't. Have you heard of Taryn Brumfitt? I totally recommend her documentary "Embrace". Look into her social media posts as well. She encourages women to embrace their beauty, no matter what it looks like. Because guess what? You are beautiful, I can guarantee that. Asymmetrical face? Drooping nose when you smile and no Hollywood smile? Still beautiful, if not more beautiful than if your face was indeed symmetrical. Because ultimately, you are you. You are unique. And you are worthy. And it doesn't matter what anyone says or thinks, and certainly not that silly 7 year old boy.
I encourage you, as I always do in my replies, to speak up and talk to others about what you are feeling, so that you can get some help changing the way you are thinking. It's okay that you are insecure. Many people feel that way. I feel like that much of the time. But it's about recognising these thoughts as ones of insecurity and not ones of truth. A psychologist might be able to help you with that, a counsellor or a best friend. You shouldn't have to live your life not feeling beautiful just because of society and because of personal insecurities, and the good news is, you can get help. I promise. Countless young women have been there, and have managed to change their thinking. So don't lose hope, and hang in there. If it's any worth, I'm confident you're beautiful because you come across as very kind, and I believe every kind woman is a beautiful woman.
“A rose can never be a sunflower, and a sunflower can never be a rose. All flowers are beautiful in their own way, and that’s like women too. I want to encourage women to embrace their own uniqueness.” Miranda Kerr
“Character. Strength. Intelligence. Style. That makes beauty.” – Diane Von Furstenberg
Wishing you all the best.