What about heat?
How is it heated? What are the temps? Are you using a digitl thermometer?
As the other poster stated, sand is dangerous for leos under a year old - and calci-sand is dangerous for leos of any age. Its been shown over and over again to cause impactions that sometimes even result in death, it also can scratch your leo because its rough and can cause eye infections etc. If she has a sore on her nose the calci-sand can also further an infection.
Swtich out the calci-sand, safe options include paper towels, tile, non adhesive shelf liner, or reptile carpet.
She should also have three hides - one on the warm side, one on the cool side, and a humid hide. A humid hide can be constructed out of a tupperware container with a hole cut in the side, lined with damp paper towels. This aids with shedding.
If you could get a pic that would be very useful.
Definately change the substrate, check the temps and add a humid hide. Monitor the mouth carefully - mouthrot can sometimes appear as a "scratch" or "scab" to start with.
If its just a minor abrasion it should heal pretty quickly on its own, providing her temps are good and the substrate is cheanged, etc. If it does not heal or begins to look worse then she should see a herp vet asap.
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