I know it's unfortunate, but if your mum is scared of animals then maybe you shouldn't get a hamster. You have to respect her and the rules she has put in place. If there is some way you can convince her that animals aren't all that bad though, then I would try to get a hamster. But first you need her to accept animals for her to even consider getting one as a pet. I would recommend showing them a cute YouTube video or something similar. If you have a friend who has a pet, get them to talk about their experience. Good luck.