I can't add much to what the others have said. Other than doing OOH is the norm. There's a growing list of exceptions in small animal practice, but the majority do, do OOH.
If you're not sure about being a vet, I would not apply, a decent propotion of people drop out because they don't REALLY want to be a vet once they realise what the course is like (9-5, 5 days a week) and that the rewards for the end aren't great financially.