I have pain in my hand which have had nerve conduction study showed no carpel tunnel , get bad cramps & pain in thumb & fingers , what could this be?

Mild arthritis: Trigger fingers, circulation issues, peripheral neuropathy, tendinitis , raynauds as well as metabolic or endocrine issues r inflammatory arthritis al come to mind. In short there ae a lot of things that can cause these vague symptoms.

Other options...: Although carpal tunnel is commonly noted on nerve studies, there are some cases where patients have symptoms of carpal tunnel but the tests remain negative. The best way to determine is with a good physical exam by a health care provider. Another item that can cause similar symptoms are radial artery problems at the wrist - it is worth evaluation by a good health care provider.