Really to hard to tell from the photos. Mouth rot is usually caused by stress and dirty cage conditions/nasty water or a lodged piece of substrate in the mouth. You said she ate on Tuesday. Do you feed live or F/T? It is not uncommon for animals to injure their mouths while feeding. I have seen them slam the side of a tub so hard the lower jaw swelled up. I have also had them hit the end of the feeding tongs. Either way I would do a good cage cleaning and replace the substrate with paper towel. Clean and refill the water bowl. Try and let him or her have some alone time. The less you mess/stress him the better. The peroxide once or twice a day should be more then enough to stave off any infection until and most importantly you get him to the vet. Good luck and don't worry. Jeff