Was this wrong for me to do???

Okay so I am getting married next year and I am 20 and my fiance is 19. Well he has a very close relationship with his mother and I think it's sweet because that plays a big part in to why he respects me so much but lately the fact that he still refers and even calls his mother "mommy" just rubs me the wrong way. I mean when we're together and apart from his mother he acts like the mature guy who I am ready to spend the rest of my life with, but when we're around his mother he turns into this huge ass baby and he wants all this unneeded attention from me and his mother it's like so annoying. So after being fed up with it for more than a while I told him that he should really work on being less of a baby when his mother's around and to stop calling her "mommy" I mean he even has her programmed in his phone as "mommy" I just don't think a grown man should still be calling his mother mommy esp. when he's about to be married. I mean my biggest fear is that he will want to bring her into our marital situation because he already tells her everything but I told him there's a limit and he seemed okay with it and even said he would work on it but does anyone think I shouldn't have told him not to do that? I mean it's good that they're close but he's about to have a wife so I think he should of detached himself from the ... by now.

You're entitled to your opinion

From what you've mentioned above, I don't think you're wrong to mention this to your fiance. However, the two of you are still quite young and men don't mature as fast as women!
It is a great thing that he is close to his mother, but you should see her as an ally rather than someone that you expect your fiance to drop just because he is going to get married. Are your fears that he will "bring her into the marital situation" caused by some specific things that have already happened? and if so, maybe you should speak to him directly about that

Thanks

I don't want him to drop her by no means I just want him to depend more on himself for certain things. He has often told her things about us that should just stay between us and I don't want him running to her all time when we're married.