Tail irregularities in Eastern Ribbon Snake

[hclivess]

Greetings, here are pictures of bums that my East Ribbon Snake has on tail, is it normal or sign of some ilness?

There are three bumps and near the very tip the bottom part of the tail appears to be missing. There are the photographs in the attachment, thank you in advance for any help provided. I never had a snake before in my life and have this one only for a week, so I have no idea whether to take him/her to the vet.