You’re absolutely right to trust your instincts; please head to the emergency vet as soon as possible. It’s also very important not to try inducing vomiting at home, as this can cause more harm than good. That decision is best made by a veterinarian based on your dog’s specific situation. In addition, if you're visiting a clinic that isn’t your usual one, bringing along any medical records (like vaccination or deworming history) can be really helpful to the professionals who attend to your dog.