I had pain in my arm since yesterday and it's from my wrist to elbow and in my forearm and in hand . do u have any suggestions on what it could be ?

Neck or nerve?: I'll be question is whether you may have injured your neck or your arm… If no injury, then you may have pinched a nerve which produces radiating pain along the course of the nerve. Common pinch points include the neck, elbow, and wrist.examples of these include carpal and cubital tunnel syndrome's and cervical disc disease

Wrist/elbow pain: Did you have any trauma or injury? if not may be carpal tunnel, thoracic outlet or other repetitive stress, in endemic areas check for lyme, sometimes food intolerences, rarely an arthritis. Also check TSH, Consider NSAIDS ( motrin , ibuprofen) if not allergic, rest arms in neutral position ( like playing piano with hands slightly flexed. Wrist support may help f/u w/doc