Is Something Wrong With Me?

Ok so I've only just turned 18 like a week or so ago, all I want is to have a baby except my boyfriend ain't ready just yet, although we have talked about it.. Is it wrong, or am I just being selfish.. I've wanted to be a mother for well over 2 years now, I know I'm young and most people wouldn't agree on it.. I probably wouldn't even make a good mother but I love kids, I have a nephew and neice, my mum looks after babies and I love it so much, I couldn't imagine not having kids ever. Grahhhh, I'm so confused/frustrated.. It's even brought back my depression. I want to conceive so badly. Is it wrong of me?