Looks like a normal to me!
As far as determining age and sex... Do you have a weight and length? These can give you approximate ages, but it'll still be hard to tell as these can vary from snake to snake. And as far as I know, there's not really an accurate way to tell sex visually for ball pythons (except that females tend to put on a bit more weight and males stay leaner). Probing is going to be your best bet. I'd set up a vet appointment for that, as well as a general check up. Can't hurt!