Sir, the first thing you should know is that there are different types of assays or test available to test serum creatinine level. So that's the reason there are different normal range mentioned in the laboratories you got it checked and again the creatinine level varies if you are dehydrated, had high protein food,certain drugs like NSAIDS,cimetidine,cephalosporins etc before giving your blood sample for the test,so kindly check those things. Generally people having kidney disease will complain of lower backache, swelling in the face,generalised weakness, altered blood pressure etc. If you have any such symptoms kindly consult a physician.