Birth charts don't determine beauty. What they do show is, if you have issues with your own perception of yourself, what the nature of those issues is. For body image issues, the place to look is the second house.
Your second house is ruled by your Moon (rules the sign Cancer), and your Moon is currently being transited by Jupiter and Pluto. Jupiter makes whatever it's transiting seem very, very big. Pluto brings out issues of power and disempowerment. Moon in general speaks to sense of personal security and worth.
If you are feeling insecure about your looks--which is a very common way to feel in early adolescence--those transits make that insecurity very, very big. So big that you might be disempowering yourself over it. You might feel, for example, that you can't have a life until you make yourself beautiful, but you don't know how to make yourself beautiful. You might feel compelled to lose weight (if you do, beware: Capricorn Moon is very good at self restriction, and when Pluto is in the picture, and Jupiter too, self restriction very easily turns into an eating disorder).
Mars in your second house, in a water grand trine with Venus and Uranus with Saturn turning it all into a kite, speaks to the emotionality of your self perceptions, and the Saturn placement might further incline you to self restriction and self criticism. These placements could also serve to make you wonderfully creative, if you follow them that way.