Hello and welcome to HCM Well, these symptoms are suggesting neurologic issues and usually there is a disorder of peripheral nerves in arms and hands.It is also called radiculopathyy. It suggests entrapment of a nerve rootin your cervical spine in its origin or course. This may be the cause of your arm numbness It can be caused by lifting weights, episodes of over-exertion during work, long hours on computer, inappropriate posture while sleeping or sitting, lack of proper nutrition-exercises-rest-recreation or any other relevant past medical history. If it has been persistent or even increasing since few days, you need to visit your orthopaedician. Depending upon the clinical findings they might ask you to get an MRI done, which shall help establish a diagnosis and in turn allow one to formulate a treatment plan. It may be in most cases temporary and self limiting illness that usually the treatment goes in following lines: rest, lifestyle modifications (namely- avoiding pillow while sleeping, following a healthy diet plan, maintaining suitable posture while working on computer/driving, avoiding any activity that strikes neck discomfort). In case the pain is not adequately relieved with the present treatment then you may need oral muscle relaxants and methylcobalamnin supplements for proper relief. I do hope that you have found something helpful and I will be glad to answer any further query.