I have twitching in my arm between my wrist and my elbow some pain and pressure what could this be?

Twitching, of course: Only muscles twitch. Muscles twitch because of the muscle itself or because of the nerve that supplies it. Localized muscle twitching is almost certainly due to a nerve problem. The three major nerves in the forearm are the median, ulnar and radial nerves. It is likely a problem with one of them, more likely median or ulnar.