I Have Been Itching On My Upper Back, When I

i have been itching on my upper back, when i scratch i felt the rash and bleed. Also after going to the doctor I told him my feet was tingling, his answer was all your blood work turn out goods I disappointed that my blood work turn out good. I said no, but my feet is tingling, I ask him what was vitamin D level. He said he will check it next time. Still having problem.