It's totally normal to start getting the baby itch in your twenties. It's just a normal biological reaction to all the hormones your body produces when you are fertile. It only gets worse! But, luckily women in our society know enough now to be able to at least attempt to plan our families, so just because your body wants a baby doesn't mean your brain has to acquiesce. If I had listened to my hormones, I would have had about 3 or 4 kids by now. I've been married a while and we made the conscious decision to delay having kids until we had spent a lot of time nurturing our own marriage (and having a lot of childless fun!). Now our lives are about to change for the better, I think, but I also know that the days of staying out all night, sleeping in every weekend, traveling on a whim, etc are pretty much going to be over. So I'm glad I had my early 20s with all that freedom.
I think baby names are one way that we can channel those maternal feelings when the time is not right in real life (no stable partner, shaky finances, having growing up to do). Sure, you can be a good parent without having those things, but it certainly makes it a lot harder. So name away, but enjoy your 20s!