I just waited with my first DD, as the current parenting experts insist is the right thing to do. Every time I brought up my concerns with the pediatricians, they just said to give her time, that she would do it. HA! She was FOUR before I finally said enough was enough and forced the issue. It took several weeks because she was very afraid to release BMs on the potty. She stopped wearing pull-ups to bed when she was five.
With my second DD, I had learned my lesson, and pushed it at 2.5 years. She was completely trained in a couple weeks, including nights.
Good luck! Your DD is plenty young. If you don't think she is ready, it is fine to wait. However, as someone who has struggled with training a child at 4 and a child at 2.5, I can tell you that younger is easier!!
Peggy