why this career?

since I was a child I really loved animals, specifically the big ones, like horses, cows, wolves, etc, so... I told my mom and my dad that I wanted to be veterinarian.
But also I wanted to study medicine, but I realized that I dont like people, and that the animals were more cute.
I really don't know where I want to work, but, I guess I like surgery, but in big animals, like cows, horses, sheeps, and others.
Also, I really like small animals, but I dont know, people thinks that small animals were the only who needs atention, and the big animals were food, and that is not how I think; that's the reason why I prefer tu work with big animals, than the smallest ones.
But it can change with time and new experiences, so... what I want now, can be completely different with what I will want in two more years.