My son is almost 15 months, and he doesn't have any words yet either. He makes a few babbling sounds sometimes, and often makes little quiet grunting noises, but really isn't the loudest of children. Our pediatrician said that while ideally she likes to hear a few words at this point, it isn't major cause for concern yet that he isn't speaking at all.
She said she would be worried if he didn't seem to understand anything we said to him and had no apparent desire to communicate at all - but he does.
For example:
If I hold up a banana and ask if he wants some, he'll run over with a smile, hand waving in the air ready to grab his favourite snack. Do the same with a yogurt (which he detests) and he'll ignore me.
Open a picture book and ask him where the cow is, and he'll point to it and look up at me and laugh if I make a funny mooing noise.
Ask him if he would like to go out in the yard to play with his ball, and he'll probably go get his ball.
Tell him to say bye to someone and he will usually stick up a hand and wave.
Does your daughter do things like that? If so, then I really wouldn't worry yet.