I liked to abuse animals.
How did you abuse animals?
I used to put certain animals in a box and leave them there for a long while. I also used to hit some animals
Abusing animals is reprehensible behavior and needs to be addressed even if the behavior is in the past. You need to immediately see a therapist and admit your actions so that the desire to behave this way completely stops.
It was only a phase I was going through but sometimes the urges come up again and I go on the hunt.
It sounds like your need to abuse animals isn't really in the past anymore and abuse is wrong. You need to give up the abusive behaviours, atone for your actions and find a way to heal those old karmic actions.