Not to be a jerk. But if you suffer from that many phsychological problems, are you really ready for a baby?
But that is'nt my decision or the question at hand. I think you should hold back on smoking for the first 6 months atleast, just to be safe like others have said. And thats when growth and development primarily takes place. Because your kid is forever. So the question is; Which ones more important to you, Weed or your childs health?