I am 6 months postpartum. During my pregnancy I was unable to gain weight and gained only 5 kgs during whole pregnancy.  After delivery i lost around  8-10 kgs within 3 months and continuously feel extremely fatigued, constipated, looking very thin, sunken eyes. I am exclusively breastfeeding and taking a proper diet but still not having much effect. I am having health anxiety because of this and feeling very low. Is it normal to lose this much weight while breastfeeding and what should I do about it.