Can a seizure be caused by pain and shock?

Yes in some people: Yes some people are prone to and I have seen it first hand when I was drawing blood from my patients and I remember at least three times when patients went in to a full blown seizure with no history of seizure disorder But any seizure needs to be investigated for Epilepsy.Some patients with seizure disorder can get seizures due to pain or shock. and that is true

Depends: This depends on what you mean by a seizure. An electrical seizure (two or more make the definition of epilepsy) is not provoked by pain or shock. But symptoms that look like a seizure can be caused by pain, shock, past trauma, malingering, etc. These are called non-epileptic seizures, and in them, the brain waves do not show significant aberrant discharges.