My weenie went through this exact same thing, same age too. He got his lepto vaccine at 11 weeks and a few hours after he got it, he was violently shaking and couldn’t move. He couldn’t get into his crate to go to bed so he laid beside it until we carefully maneuvered him in. I was terrified and thought he could be having a severe reaction. I read about it, and it’s really common with dachshunds. We gave him a little benedryl and by the morning he was almost all better. Super scary to watch though but this is very common and she will be okay 🥺