looking at your pictures that you posted the snake looks to have some injuries on its sides as well either from rubbing or from improperly trying to remove shed. I would say if you are soaking the snake you also do a betadine soak ( you can find this at Walmart) add it to the water it should look like watery tea color. as far as the feeding i don’t know how long you have had the snake but when first receiving a snake you want to allow atleast a week before you even think to feed or mess with the snake. Ball pythons can be picky eaters if they are being transitioned from live to f/t. This might take a while but the snake will eat. Also ball pythons will at times go on hunger strikes and they might not feed for a few weeks. Recommend taking snake to a vet if you are really concerned.
When purchasing a ball python as well you want to not only inspect the snake but you want really get the feel from the breeder. If you don’t get a good warm fuzzy feeling about the breeder rule of thumb don’t buy from them. I would question the genetics of the snake as well. I have pastels and super pastels and I’m not really seeing it. In future ball python purchases I would say use www.morphmarket.com. Or go to a local reptile show. I found in going to reptile shows when I started my collection. I made great connections with some experienced breeders and hobbyists that know there stuff and want to help as they are local.