If your sure you want to be a vet get those grades up now:)
Vet schools are very competative and hard to get into, so the better your grades the better yuor chance is. It also helps if you can get in and work for a vet. I have friends who even volunteered so they could get their foot in the door.
I wanted to do something with animnals but I couldn't find anything that paid well enough that wasn't a vet. So I became an RN. my reasoning is I can work three twleves and make enough to have all my pets and still do my rescue work and I'll have some extra time.
If I have any beliefs about immortality, it is that certain dogs I have known will go to heaven, and very, very few persons -James Thurber