Wierd leopard gecko behavior?

I have had three leopard geckos for a couple of years now, and they all get along fine. I feed them 6 giant meal worms a day. One has not been eating but has a surprisingly fat tail, healthy fat. She( i think it female) is always in the same place under thier log and she doesn't ever seam to move. When ever I try to move her she runs real fast and tries to hide. What could be wrong? Why is she fat and not eating?

Quit asking question on the internet! GET HER TO A VET BEFORE SHE DIES. If you don't know how to treat exotic pet illness, you shouldn't own them.

We don't have a ton of money right now, were broke. I want to be sure that she needs a vet before I take her to one. I don't know where one even is in my area. She was a gift anyway, so it's not like I'm wasting money if she does die,(Which I don't want her to, I do try to keep them in the best of health, don't think I don't care about them) but I am keeping tabs on her and I don't think she's on her deathbed yet.