female leopard geckos stop eating and dying off

2 females after laying eggs have stopped eating and dying off. These were infertile eggs. Now one other, who hasn't layed, is refusing food. We've force fed repta-aid, but eventually died. 1 developed a strange internal lump on her head. Any idea's?

Have you brought any new animals into your collection? Have you been to any reptile shows/pet stores/friends houses with reptiles/etc? Are you taking the animals to a vet or getting a necropsy done?