I woke up in the middle of the night last night because one of the arches my feet was cramping horribly. It was the kind of cramp that I sometimes experience if I stand on my tip-toes for too long. I feel like it could easily start cramping again if I stand in a specific way. This has never happened to me before! Any possible causes? What can I do to prevent this in the future? My dad thought I was either dehydrated or lacking in calcium, but I eat a lot of dairy products, and I drank two cups of tea and two bottles of water yesterday evening.