as you tell your blood report say vit. d defiencency. so you produce calcium defiencency along with that so you produce muscular cramps in your thigh. for this you have to eat calcium rich food and calcium supplement
with them. and the vit d is produce by your skin's first layer in presence of lite sun light. and with food supplement containing vit. d3.
now you skin problem about itching. it's may be erticaria so you need to consult skin specialist. for that it may be allergic reaction
with same. and take tratment.