During my pregnancy I put on 10 kgs.

I gave birth to a 4.86kg baby. And presumably, I can also account for some pregnancy weight with my placenta/amniotic fluid/increased blood volume.

When I came home from hospital (day 5), I weighed 1.5 kg more than my pre-pregnancy weight, which I was pretty pleased about, thinking that it wouldn't take me long to lose. Now ... day 10 .... I weigh 1.5kgs less than my pre-pregnancy weight.

Is it normal to lose my pregnancy weight so fast, and then some? I am breastfeeding, and worrying that I may need to eat more to keep my supply up. Or should I just count my blessings lol?