I just had a mild seizure and had walkeda 5k without drinking much water and eating salty foods?

Pin this down: At age 68 yrs, when you experience a temporary "seizure", we need to ascertain whether it was a true epileptic event, or a syncopal spell due to dehydration, or a cardiac event, or brain transient ischemic event. As might be emphasized, this is VERY important due to risk of more severe future events. Your doctor needs to be fully involved NOW. Do not delay.