I took a chewable vitamin c tablet 500 mg last night on an empty stomach and shortly after i started having pretty severe painful stomach cramps. it scared me so i ate some toast and water and hours later it still feel tender . possible the vit c?

May be: If it has subsided and is getting better, you can ignore it as Vitamin C is not likely to cause any lasting damage. Have a healthy diet, exercise 30 minutes/day, drink plenty of water daily so your urine is mostly colorless, have safe sex, no tobacco alcohol weed or street drugs. For nutrition: http://www.choosemyplate.gov/. Wish you good health!