OP, other people will care about your baby - sorry, it was badly worded. What I mean is, they won't be affected by sex/name etc.
You sound very private, and I have more sympathy after reading your second post. It's not that you begrudge his excitement it's that you just don't want to discuss your business with other people. At this point it's your body - I can understand why you were tempted to tell your friend. When thinking of it that way it's understandable. It's easier to discuss wth your own friends than a person who is a stranger to you.
But this is one of the things to consider in pregnancy, it's already involving other people. With my 1st I was self conscious and didn't want to discuss with anyone I didn't really know so on the basis of that I wouldn't have wanted DH discussing with anyone I didn't really know. With my 2nd I got it, and it wasn't about me really at all.
It's difficult OP, but try to understand he is trying to get used to things too. It isn't his body which is affected so it's hard to understand why you can't share your excitement with everyone. The name thing is a non-issue though and you need to develop thick skin and ignore opinions. Honestly, people think they can comment on a lot more than the name once you have a baby.
It'll all come right in the end, the little things won't matter so much once the baby has arrived and hopefully you'll feel more relaxed. I don't feel that your comments suggested miscarriages were anything to be ashamed of, I think they were more about how painful it would be to explain to people when grieving privately would be your preference.