MIL problems

So earlier tonight, my boyfriends mom asked him if she could put the happy news on Facebook and he told her yes. Then when he came back into the room I said um, hello? what about me? I don't think I want it up there right now I'm barely 10 weeks!! so then he had to go back to her and say never mind, it's still early and told her I don't want it up on there. She then went on to make a face, and then get all upset and ignore him. I get that she's excited but I feel like IF it's going to be up on facebook, me and my man should be the ones to announce. Am I wrong for feeling this way? It's OUR baby, and I'd like it if she would keep it off of there, at least for now. I feel like she's acting a little bit childish... I feel bad as though I'm causing drama but i mean, it's our news and I'm not comfortable putting it out there just yet. Someone tell me I'm okay for feeling like this??