I am getting pretty consistent foot cramps everytime i dive lately and was wondering if its the coldwater or if my footpockets are too big. i am wearing a 3mm bootie with my fins because the water is about 55 deg. right now, but the footpocket fits good length wise but theres a little room on the sides. should they fit tight all the way around? they cant be way too big because i can kick and swim all i want with no fin keepers and the footpocket doesnt slide on my foot nor ever come off. I drink plenty of water and dont get cramps anywhere else? any ideas?