Sure, all of us. Relationship dynamics change all the time; that is what relationships do. The changes tend to be gradual, though, so if it was something sudden it can feel unsettling, sure.
That's really all that matters; as long as you, your partner, and whoever else is involved are still feeling happy with however things are going, then don't worry so much.At first, I was a little cautious about the change but I'm ok with it
Who cares? Look at it this way: since every relationships is unique (because it's made of people, and each person is unique), then everything is rare because there is only one relationship exactly like yours.I'm new to this, so I just don't know if this is common or rare is all
Even for kinks that are "common", each person has their own variation of it that makes it completely unique.
If your dom has a dom, and all three of you feel happy and fulfilled, then all the more kudos to you, getting three people to get along like that (when getting just two to be happy can be so difficult!) However I'll tell you the same thing everyone else has; make sure you speak with your dom about your concerns and feelings; communication's even more important when you have so many people involved. Hope this helps!