Think about how you feel about you and not how you look. Try this, stop looking at yourself in the mirror for as long as you can. Mirror is a modern invention, for millions of years we did not see ourselves, only reflections of ourselves in water. Think you are a primitive being living in a jungle, how would you know you look good or bad? You can feel good about you by doing what you like and making others around you feel good about themselves. Do a good deed everyday and feel good about it. I automatically do simple things, give my seat to elderly, a pregnant woman, etc. Help anyone needing help in the street. Then walk away without expectations of returns from a favor.
Looking good and pretty is in your mind. I think everybody looks beautiful, everyone has there unique look. Physical looks don't matter as long as your inner is beautiful.