I am so scared of life.?

Truthfully, you need to make your own decision on the career that you want to be in. Your mother can't make that decision for you. Think of something that you like to do. If you got a 71% and you don't think that you can improve your grades, then you need to change your career because in order to be considered for medical school, you need to make at least a "B". I don't think that it is in your heart to become a doctor. It's your mother's dream. Just think of something that YOU want to do in life. You are an adult now, and you must make your own decisions. I know how tough science cles are because I have taken science cles before, and I am enrolled in two science cles with lab. Don't give up on your education because you are smart enough to become whatever you want to become in life.