Who is this person to you?
How old are they?
If you were talking about someone in their 20's or above I might say that they have a narcissistic personality. However you're talking about a 16 year old girl, they are many times narcissistic in nature. Since the advent of digital cameras, computer cameras, and the surge of online communities that encourage you to post pictures like facebook, and myspace....it's become second nature to most teens to take many pictures. It's not uncommon for them to take the same picture over and over again to get it "just right". I have a 16yr old and she has hundreds of pics, so do many of her friends and cousins.
I wouldn't worry about it, but what I would be concerned about is the type of pictures being taken. Some kids are sending nude or semi nude photos, not realizing that they can be copied and posted all over the internet, even on child porn sites. Once a picture like that is disseminated across the internet, there's no way to remove it.
I welcome your thoughts, let me know if you want to talk more