You got pics? I would love to see a couple pics of your snake. Also when you are comfortable with it you should probably switch him over to rats. Ball pythons are girthy snakes and require larger and slightly fattier prey items than mice. There are a few picky ball pythons that will only take mice but they tend to be on the smaller side unless the owner slips in an extra meal per week but it could still cause your snake to stay on the small side. A good rule of thumb is to feed a prey item that is as thick as the widest part of your snake. Unless its a hatchling I think hopper mice are very small. I received my cinnie when she was only a month old and she started taking rat pups for me immediately. You can order frozen thawed rats in packs of 25 or you can make a weekly trip to the pet store...