Sorry but pictures to me are unclear to see details. Some facial problems happen when scared and dive off basking area fast hitting something. Due to not having a clear zone to dive into. They also use there heads to dig into gravel pushing it out the way to investigate whats under it because they are so curious. If you use aquarium gravel that’s bad for several reasons the main one is turtles eats it and get blockages and or cuts from sharp edges. Check you setup carefully and make it turtle safe. May be a wound from something in tank , check well. Also skin problems are related to inadequate filtration. Either filter and or type of media used. Just not clear enough photo to tell for sure to me.
Babies shed the shell and skin fast so should heal well with treatment. Early stage of a classic skin fungus infection. The environment turtles live in will start a problem fast then silvadene cream will be needed ( a RX in the US). Treat before it get worst , don't wait too long , or it will turn into a full-blown fungus infection .
Cause must be determined. It does look a little deep. You must be careful being between eye and beak and a baby. Larger turtle would be treated several ways with creams and dry docking over night. But if you do with a baby that’s stressful so I would only dry dock for an hour or two a day applying a treatment a couple times a day. Use a q tip to apply a "thin” layer of cream (silvadene) it works the best , turtle will rub it off so will have to reapply often with the “short” dry docking for a baby. Do not get in it's eyes.
A go to page is here for skin problems.
http://www.austinsturtlepage.com/Care/medshell.htm
