healthy postpartum weight loss

so just a quick question.ftm here. I don't have my 6 week appt for almost another 5 weeks but am wondering about healthy weight loss. I am exclusively breastfeeding and gained 34 lbs during my pregnancy, starting at 152 with a bmi of 23.8. My baby boy is now 8 days old, weighed 8 lbs 2 oz at birth and I lost 13 lbs right after delivery. since then I have lost everything I have gained during pregnancy plus 2 lbs. so a 36 lb weight loss in 8 days. is this okay? I'm not sure if it's something I should bring up to my doctor or if that's completely normal? thanks mamas. :)