Placenta Previa

I'm 12w+1d, and after a day of cramping and bleeding, I was sure I was going to lose the baby, but turns out I have placenta previa. Any one else have this? The more I read about it the more I freak. My Dr told me no exercise, not even walking, but he was kind of vague in general. I'm at home with my 30lb toddler, what are the limits? Picking him up, carrying him upstairs? Everything makes me breathless already! I don't want to push it, I'm just not sure how to manage a toddler & rest. Eeeep.