Is it normal if he calls me by my nickname more than babe, baby,etc?

So my dude and I are just starting to get serious after a weekend trip together. Ever since, he proved himself to be more like a bf than before. We have been talking for a while now and I always questioned if we were serious but in the back of my mind, I knew we weren't exactly bf and gf but more like casually dating. So now that we're more serious, I expect us to feel more comfortable with each other, after all, its why we've been seeing each other for so long and finally getting serious. But it seems like we're still not that comfortable with calling each other like "babe" or "baby." I always refer to him as "my baby" when I talk to other pple about him but when it comes to calling him that to him, I still feel weird and so does he. He calls me more by my nickname than "babe," etc. I guess he got so used to it but at the same time, I feel like he should start getting more comfortable calling me baby or babe. I already call him baby but not to him but its prob cause if he feels weird about it, then so do I. Or we call each other our nicknames weve come up with rather than the usual terms. Is this normal? does it make a difference if he calls me more by my nickname than those other names? is that a good thing?