Anxiety will pass in time , their is nothing wrong with playing with barbies at your age. You have an imagination and the need to express it. Plus if it's something you enjoy doing , I wouldn't worry what other people have to say. When you grow up alot of things will play in factor on how much responsibility you have. You may feel better be able to talk or express you anxiety in creative ways . Maybe writing a children book that helps you explore and look at why your feeling anxiety ridden.