It depends on the name he is calling me.

My boyfriend hardly calls me by my name. Although, few times, he does, but it's just once in a while and not all the time.

So it is definitely not wrong for your boyfriend/girlfriend to call you a name other than yours. Especially if it's a beautiful sexy name.

I and my partner used to call each other with another name other than our real one. I am comfortable with this and I found it's okey for me. 

Another name for your partner comes from your love, adore and affection. So if anyone gives me some special name I would love to hear that. I have seen many who used to call each other with different names and some are really cute. Those are the sign of love for me. 

When I got angry, I don't call my partner with the special name but the regular one. So it is like a sign to show my love and affection to him. Not only girlfriend or boyfriend, it is also okey in between husband-wife or brother-sister. It's the example of love and bonding to me. 

So if someone calls you with a different name, don't feel bad or wired, accept it. It's okey to call your loved one with other names.   

Sure it's right for my girlfriend to call me a name other than my real name

But it has to be a romantic one