Daughter not talking, please help!

Hi everyone, I am looking for some reassurance from all you mommies (or daddies) out there.. my daughter is 17 months old and she still does not talk. She doesn't really say any words. She grunts a lot and talks a lot of jibber jabber but she has yet to say actual words. The closest she has got to saying an actual word is "da da" and she used to say "ma ma ma ma" all the time. She calls our dog "d-d" or "diggy" sometimes. She communicates to us by pulling on our clothes when she wants us to play with her or follow her, when we ask her if she's hungry she runs to the kitchen and stands by the cupboard where her food is, but she cannot verbally tell us what she wants. She still cries when she needs something, and we just guess what it is. I am so frustrated and worried that she is behind on talking! I've read that most babies are saying a lot of words and copying everything they hear by the time they are 18 months old. She's not saying any words. I feel like I'm not doing enough, or doing something wrong. Please give me some encouraging advice! Thank you