HI guys, I recently rescued a little Ball Python who had prolapsed twice. I have no clue how old he is, but I've known him since november. I adopted him in february. He is 109 grams. Recently he had an edema on his side and I brought him into the vet but they didnt seem very experienced. When I took him out today to give him his injection for his antibiotics, his skin was super wrinkled and dry looking. He's been shedding and flaking little pieces off when I soaked him. He went a really long time without shedding (a couple of months) because he didnt eat when recovering from the prolapse. He's been refusing food this past week because I'm assuming the meds and shedding.

I have a few major questions:
1. His humidity is a big struggle. It stays at 10% and I dont know what substrate to use to keep it up. He has 3 water dishes in his 20 gallon tank (I know, small for now, but he's so tiny still).
2. Should I be really concerned about this wrinkling? what should I do to fix it?
3. He hasnt gained weight. I feed him 1-2 mice pinkies every 4 or so days. Should I be doing something else?

This is him as of yesterday, his name is Frederick.