Ah, well! Does anybody really understand anybody else? We hear so often that someone else "doesn't understand me," but I don't think anyone else is on the planet to understand us-- least of all our parents and teachers, who are of a different generation.
The main thing is to try to understand yourself.
You have a strong Saturn-Aquarius nature, with a lot of the air element in your chart. Oftentimes people with this emphasis make good scientists and engineers. These may not seem like "girl" fields to you at this time, but the world is changing in terms of career opportunities for women, so I would encourage you to explore them. Your approach to life is both mental/intellectual and practical.
The 12th house also rules hospitals so you might wish to consider a medical career. Your chart suggests that you are actually an ambitious person, so it is a good idea to consider a career that will allow for personal and professional growth.
You may feel very serious about life, at a time when girls your age are obsessed with parties, clothes, boys, &c. If so, this only makes you ahead of your time.
With most of your planets on the east side of your chart, you need to be out and doing things to manifest your potential, not simply adapting quietly to whatever life seems to hand you.
With your sun and stellium in the 12th house, you are probably a very private person. You may actually prefer to spend time alone. And this is fine, provided you don't cut yourself off from other people who care about you or who would like you to befriend them.
Planets in our 12th house are ones we don't understand very much, although they may be very obvious to everyone else around us. The sun is your sense of self, so it may be hard for you to get a clear reading on who you really are. Then with Saturn squaring your sun, you may suffer from low self-esteem, feeling that it is hard for you to achieve your potential.
But keep in mind that just because you feel this way does not mean that anything is objectively wrong with you! Only that you are apt to be very hard on yourself.
I think you do have a rich imagination, with that Neptune conjunct Venus, but it needs to express itself in ways compatible with the sign of Capricorn and its ruler Saturn. I wonder if you would enjoy gardening-- perhaps something you can do indoors in a small space like container gardening or bonsai. Perhaps you would enjoy making stained glass pieces. With Mercury trine Saturn, you can be a very careful, exacting thinker; and may be good with your hands.
