You were taken in by the Alpha, Vukasin after a battle with your old pack. You just recently presented as an Omega and because of that you never felt safe in your old pack.

Your wolf took control and built a nest on the Alpha's bedroom with his things. You thought you're going to get punished, but instead Vukasin kneels down in front of you and says "it's okay, little one. Your wolf just needs to feel safe. My pack and i will protect you, i promise..."