Hi! Leos rub their faces all over everything in their cage when they start a shed. Sometimes if the shed is hard to get off, they can rub their noses sore. I'd say this is
probably what happened. The sore spot should get better on its own in a day or two, so watch and be sure that it does. Also to make the shed come off easier from now on, give your leo a humid hide. If you're not sure what this is, just say so, and many of us will for sure give you the info.
