900 years old eh? Possible explanations:
1) The force is strong with you
2) You found the philosopher's stone
3) You are a Highlander; kunoichi MacLeod of the clan Macleod.
4) In fact you come from the future, in an era when genetic and surgical treatments prolong life.
5) You're an alien. Also known as the second category that only exists on the internet, along with males.
6) YOU'RE JUST THAT AWESOME