On a serious note, if you are going to be around a new crowd, why don't you find a pet name and introduce yourself as that? I grew up with a Catherine who was Cappy and a girl named Boots. It could be Winter. Anything! You don't need to legally change it.
I know someone who did this, at the exact same age as you are contemplating doing it.
She and I went to high school together. We were the only two Kristens in the school. I ran into her the year after high school and rushed up and said "Hey Kristen! So good to see you." She was with some new college friends. She awkwardly said "Actually, my name is Shana now".
I'm going to give it to you straight - it really made me feel weird. To this day, when I think about that event, I sort of shake my head. So many reasons. 1) A name isn't something you put on like a new fashion. 2) It seems a little self-indulgent to rename yourself. 3) Dude. She wasn't Shana. She was Kristen. I'd known her for years. Whoever Shana was was a fraud.
I get not loving your name. I bet you dollars to donuts about 95% of the population have disliked their own name at some point in their lives. Kristen isn't my favourite name. It wouldn't have been my choice for myself. But it's a part of my fabric and it's the first gift my parents gave me. I can't imagine my mother's feelings if I decided to become something I found more fashionable. I can't imagine my daughter turning around one day and telling me she was no longer Virginia and now she was going to be known as Lily.
I remember a conversation with one of my students not too long ago - he had legally changed his name, and was in the process of legally changing his gender. His parents refused to acknowledge his new name, and continued to call him by the name they had given him at birth. It invalidated his identity, and outed him to anyone in the vicinity (his name at birth was very feminine). But more importantly, it was incredibly disrespectful. By using his old name, they were claiming that they knew him, and knew his identity, better than he knew himself. They were doing it to exert power over him, to "put him in his place" as it were.
I wouldn't change my name, but if one of my children grew up and changed their name, I would expect others to respect my child's name change. Otherwise I'm sure I'd have to turn into Mama Bear and protect my cub, and trust me, that isn't a persona that would suit me at all.