Does my character sound like a mary sue?

I recently created a character. Her name is Japanese but that is only because she comes from Japan. She has very plain looking hair and a very plain eye colour. She is also built very much like a boy, but she later becomes more feminine looking as she matures. Though not stunningly beautiful, she has been described as quite good looking. She is also very intelligent,prodigy like even with a cynical, manipulative personality. She also tends to lie a lot to save her life and is somewhat a coward that would betray her friends though she does become a little braver as the story progresses. She is also very good at games from luck games to strategical games but she has lost a few times. She is also a terrible cook and is horrible at household chores but excels more in martial arts and athletics. Though always lying, she tends to be truthful in the most inappropriate times, accidently offending her friends by telling them that they look ugly in a certain dress. Because of this she is very easily disliked and has few friends but she does improve a little as the story progresses. She has her fair share of phobias and fears and just to make things clear... she is human. Not all her weaknesses will every disappear. She does not fall in love and I am unclear as to if she should. She lives by herself and gains money through a series of part time jobs. At the beggining of the story, she is 12 and I plan to end it when she is 16. She has a few hobbies such as art and meditating. Also I made her very attractive when she matures, do you think she's a mary sue? She is my main character and I want to make sure. This is original fiction.