Re: Kidney's sore, Stomach garling/sore,black stools...
Soreness in your kidneys and stomach could be caused by inflammation. If that's what it is, it's known as "Wegener's granulomatosis" (WG). It's rare and only affects 1 in 20,000 to 30,000 people. It can affect tissues almost anywhere in the body. When it affects blood vessels it's called "vasculitis".
There are various tests used to establish a diagnosis: blood tests, urine tests, x-rays, and biopsy, for example.
On the other hand, it might be something else like an infection. The best thing would be to see a doctor.