Is it normal for a 15 year old to want a baby?

Yes, I think its quite normal. Maybe if you have relatives or families you know with a baby, you could ask to visit and help care for them sometimes. Or see if your school do a childcare course with the interactive baby dolls you can get that you have to take care of. This would help you to learn the responsibility involved of having to care for a baby. Either way, you would also satisfy your need to want to dress up and play with dolls or babies, and it would help the person whose baby you are helping to care for to get a break. It is a stage, and it will pass. have fun with it while it lasts and don't worry about it. You are being very sensible about making it clear that you don't want a baby yet. As much fun as they can be, they are also extremely hard work and an enormous responsibility. Being able to share that responsibility with someone who has a baby is a pretty good substitute in the mean time, and a sensible way to deal with this phase until it passes.