What do to for pinch nerve in arms?

Diagnosis ??? "pinched nerve" means someone is guessing but has no clue. Which nerve? Pinched or swollen? Where? How long? What is pinching it? See a reputable neurologist, get EMG and nerve conduction velocity testing. Pinpoint the diagnosis (exact identification of the problem). Treatment may include fixing hypothyroidism, controlling diabetes, removing a cervical disc, carpal tunnel surgery, ulnar release..
Radiculopathy. Radiating arm pain and a feeling of tightness are common symptoms of radiculpathy... Stemming from compression on the nerve root(s) in your neck. It can be due to a disc bulge- or herniation, slight instability or deformity or bone-spur formation and arthritis... Physical therapy with cervical traction can help, including exercises and anti-inflammaroties. Try that for few weeks to see how it goes.