That could be just a flashback but, it sounds to me more like a psychogenic seizure - not epilepsy but an EEG would tell you that and either way, it shouldn't be ignored medically.

The reason I hesitate to call it a simple flashback is the disorientation afterwards, that is all too common post-ictal with seizures.

Certainly if it happens again, see a doctor, even psychogenic seizures can and should be treated medically.