Wait till she sheds and see if it's still there. I imagine it won't be. In the meantime you can just use a Q-tip to apply betadine to it if you're really worried; it's just an antiseptic, so it'll be beneficial for both injuries and infections.
Doesn't look like scale rot though. That's usually on the belly, and typically shows up between the scales and not just on one scale. Plus, it's typically caused by wet bedding, so unless you keep her bedding soaked it's probably not that.