Sulfur crested atoo?

we recently took one in, we think it's a female, no idea on age, she was found in the aftermath of a cyclone, half her crest, tail and all the feathers under her wings are gone, she had that many mites on her it wasn't funny, since solving that problem for her she has become the most affectionate bird, she doesn't bite or chew anything, doesn't scream and doesn't seem to have lost any feathers in the last 3 weeks, her beak however seems to be overgrown a bit and she seems to have trouble eating some types of seeds, and some of her new feathers are just coming up as little lumps which we need to remove for her, it's causes her pain thats obvious but she allows it, would these lumps just be because she can't preen properly because of her beak or some sort of effect from the mites or something else?