Hmmmm does not look like the typical thermal burn... Very odd. If it is a thermal burn then silver sulfadiazine cream can be used topically on it... But I will tag in others with more experience then me. @kinyonga@JacksJill
This could be a thermal burn or infection, although blisters from burns are rare in chams. From some other thread I saw, neosporin should get it healed nicely.