Well with my first I lost 25lbs the first week. Its expected that you lose all the baby weight plus breastfeeding burns 600 calories a day.
Well idk about you but i gained a lot of weightfrom water retention. I was a balloon. Lol by the time it was all gone i lost 30lbs
Baby weighed 10
Im not sure how much placenta and amnioticfluid weighed and plus any weight you lose pp i think that that is safe. As far as breastfeeding as long as your eating 1800 calories minimum you should be good. If your continueing to lose weight that rapidl then it is considered "unhealthy"