I use to have trouble with my perception of how others see me; that can be colored by you, rather than the other people, too. I would look around at what people you are with and why; hanging with people who are negative and actively appear to dislike you doesn't do anything for one's self-esteem. I know when I was a teenager, I had a classmate who disliked me but I later realized she was jealous of me, did not know "me" but just what she thought I represented. That can happen a lot when one is younger I think. Before we meet many people from all walks of life, it can be easy to have preconceived notions of what they are going to be "like" from their clothes, who they are with, what they say/do, etc. and harder to keep an open mind.