Keep that opening moist as you are doing with the paper towels in the cage and such. Is that a large blockage of urinate (the white spot) in there? I would keep her in a few inches of warm water for a while and see what happens. It looks to me like shes blocked up, and that has to come out before she tucks back in.
If it was caused by a large turd, it could have been constipation or overfeeding. If she was malnourished her body may not be adjusted to handling a normal amount of food quite yet (just assumptions/guesses here). I'd def see a vet.