Why must people try and start things?

So today I got a call from my mom. It started out casual, but ended in her getting mad at me. She joked about beating us to the hospital and I told her I have decided not to call anyone about my being in labor until after my SO and I are in the hospital and settled in a room. For one, if I go in too early (I am a FTM) and they don't emit me yet, there is no point in anyone else being up there yet. Second, I would like a chance to settle in my room before being bombarded by family. When I tried to explain this to my mom, she flipped out and tried to demand that I call her as soon as I get into the car to leave for the hospital. I told her no, she will be called when I am in the room. She then proceeded to talk about how I am keeping her from being there and she wants to be there. What? No? I have promised to have both my mom, my SO's mom and my SO in the delivery room with me. I just want a few moments to myself and my boyfriend before labor really kick starts. I have half the mind to just have it be my SO and I in the room now because I don't want and or need bullshit drama while I am trying to have my baby. Am I being selfish? I feel like my request is really fair. I understand how excited everyone is for our daughters arrival and I am so thankful for the support we have. I don't want to seem ungrateful, but I feel like what I have decided really isn't asking for much. I really don't know what the point of me writing this is. I guess I'm just upset and venting. I'm so nervous and anxious already to have my little girl. She could come any day now! I really don't want and or need any of this right now. I don't need someone trying to make me feel bad for wanting to do things my way.