I can't say this to my family

So I'm 25, I'm single and my biological clock is ticking. I don't really have any serious responsibilities, I work and have a car. I bounce around from place to place. Never really stay anywhere for too long. I can't seem to stay in one place. Now here's where I'm having issues. I can't stop thinking about having a baby. This has been going on for weeks and I haven't talked to anybody about it but sometimes when I'm alone I just think of how badly I want one. I know I'm in no position to have a baby. I smoke pot everyday! I lose my car keys all the time. I'm always late for everything. But for some reason the idea of being able to say to my parents that they will be grandparents and so on and so fourth, all my friends have their little families and I'm just single with my car. I don't even have any pets or my own place. And most of all I lack the most important thing of all, a person to have a baby with. Sometimes I wish I could just find one somewhere.