What is wrong with being unsatisfied with being a mother?

In one of my previous questions some people seemed to take offence at what I said. Is it common for people to think you have a bad attitude because you are looking forward to your kids going to school so that you can have a life outside them? I am confused as to why mothers are supposed to be overjoyed to spend every day with their children? I LOVE my daughter to pieces but being at home doing housework and watching TV is BORING when you do it every single day (for me at least). Isn't it possible that there are different types of mothers and that I am not a bad mother or a mother that doesnt deserve children just because I see my baby girl as a bit of an obstacle? I have never been into children really but I love my daughter and I would love another child but at the same time I am young and want to acheive other things too. Please be nice I am a sensitive person