I found these on him a couple days ago. They are strange grey spots, each an odd shape. They seem to be blister-like, they've risen from the surface of his skin, and have since opened. He's acting completely normal, other I than the fact I can tell these are bothering him. I have applied some aloe vera diluted water to try and help. What else should I do? I have no clue what may have caused this. Any ideas?