At such a young age, babies like to comfort suck. Remember that the world is a scary place for a baby, and I htink it's important to help it feel secure however possible. I was against dummies, but someone advised me to get a couple just in case. I now have about 8 because I couldn't live without them.
The only thing I would say is not to give your LO a dummy if they're perfectly happy without one, because it only encourages them to get used to having one in their mouth, and once she starts gurgling, a dummy will stop her chatting to you, and therefore limit your interaction. I personally don't see a problem if a dummy is only used when LO is unsettled, and if she drops it at night, I will take it away from her.