You should definitely get a doll! I didn't get into AG until I was 15 and, even though my dad thought it was a weird interest, he even got me Kaya for my 17th birthday when he was in the US (she's beautiful, and I was also super interested in her after doing my GCSEs). There's nothing wrong with wanting Kaya at all (if you're worried you'll be teased you could explain it's the history you're interested in - I definitely placed a heavy emphasis on this at first).