well, I have nothing to say, that has anything to do with replies I have read. I want to focus on your post.
Unless I am misunderstanding, I don't think you were asking anyone's opinion about whether you should smoke or not.
I thought you were asking what ppl thought, about your experience with your baby, and then with that woman.
It sounds to me like you sorted out the different things. You mentioned that the baby isn't quite strong enough to sit up in the cart...that shows you have given some thought to it, so you probably are going to do it differently, until she is. Once you saw that she was falling over, you picked her up, etc.
You held your tongue, until this rude, know it all...and I say that, bc she may have had concerns, but she blew it! Somewhere in all that, she may have had real concern for your child, but her 'concern' got lost, in the way she *itched and moaned at you and threatened, etc.
You had your ac turned on, and were standing right by the car, when she showed up again!
It's none of her business, how old you are, and certainly none of her business if you are married either. Besides, how would she know? Do you know her? Have you ever seen her before? She sounds like she has issues, and a lot of gall.
I am not saying, that any of us, should look the other way, if we see, 'real', neglect, but there are better ways to handle things, than this woman chose. Ask yourself, what you think you should do differently in the future, and let that be your guide, and try to forget this woman. You sound like every new mother out there. Your living and learning, and your baby is being taken care of and loved. take care. :D