Friends, Growing Up, and Life?

I am starting Grade 10 in September and I began to think about what should I do to change. In past grades I used to be so social and more open but in grade 9 I reinvented myself cause I found out about cliques and friendships that never last, so I began to be less social and more to myself and "independent". In high school I actually acted like a child cause I was afraid of growing up; Losing the light I used to see, becoming to serious, and facing the pain of life (being a careless child seems more easy). Lastly my personality is very different from most of the people from high school, for one thing I actually smile (not many guys do), I act like I am grade 5-6, im not very athletic, and I am very vulnerable and open. People see me very approachable and nice, but I notice besides all these I feel like I can't keep up with the people in High School. like they are more darker and like in their own cliques. SO basically Im asking is. Should I change for grade 10? Should I be more shy and serious?Should I stay a child or become a teenager?And should I stop pushing people out of my life?