How do i help my chihuahua with seizures?

First off I would find a new vet. Your dog probably is epileptic. Seizures are often aggravated by stress which may be why the cage plays a factor. There are great epilepsy drugs that a vet can give you that will greatly reduce and even stop seizures. Also the vet can give you a shot(I forgot what it is called) that you can administer at the time of the seizure to help ease it. If the seizure goes on for five minutes or longer the dog needs to immediately see a vet. Also when you notice a seizure is occurring make sure your dog is on the ground, on top of blankets if possibly with nothing nearby that the dog can hit its head on. Good luck.