I have had three c-sections and am now pregnant with my fourth baby who will also be born via c-section. I have three sons and this one is a baby girl.
My first c-section was also unplanned. I was two weeks overdue, they induced for two days and it just wasn't happening. So, they went ahead with the c-section. Each of my births since then has been a planned c-section.
I have never had any problems with my placenta and I've never had a preemie. The only concern is that, during my last two c-sections, my doctor commented that my uterus was extremely thin. So, that's something we're going to have to keep an eye on this time so that I don't have a uterine abruption. I did ask him both times if the thin uterus meant I shouldn't have anymore children and he said no. He said that it may just be normal for me and doesn't necessarily mean I'm in any danger (but of course we'll keep watching it just in case). He said every woman is different. He's has a woman whose had 12 c-sections and she's just fine. On the other hand, he's had women who've only had 2 and can't have anymore. You just never know, I guess.
Being only 14 months old, your daughter is still within the normal range for taking those first steps - even if she were full term. I wouldn't worry a bit. Before you know it, she'll be running around so fast you won't be able to catch her! :)