What Causes Spinal Pain And Alopecia During Postpartum?

Sir im a post partum mother for a twin babies 10 months old,i have a wide range of alopecia almost the size of fist over the vault of my cranium,further more im just 37kg weight,i get severe pain down my spine and at times vertigo.Kindly suggest me whats up wrong with my hormonal balance or whether its a presumpting sign for any ailment?