I carried a heavy on my left arm and often lean on the left side in bed.  I began to notice my left arm would hurt and then I stopped carrying my heavy purse on that side and it got better.  No more pain.  I started again with the heavy purse and now the pain is in my neck and shoulder.  But since I stopped carrying my purse on that side, the pain is not there but my left arm gets num and when I massage my neck and shoulder it goes away.
Hello dear, The symptoms as mentioned in your post can be attributed to:1. Para-spinal spasm and entrapment of nerve fibers at the Cervico-dorsal region.2. Inadequate HY Chat Doctor.  Dietary deficiencies of certain nutrients like Iron, Calcium, vitamin D, Vitamin B12, Folic acid, etc. which help in blood formation & nerve conduction.4. Peripheral neuropathy caused due to any fluctuation in blood pressure or blood sugar level. Symptomatic relief can be obtained by intake of cervicogenic agents (like Vitamin B6, Vitamin B12, Folic acid) as well as multivitamin & multimineral supplements including iron, calcium & vitamin D needs to be added in your diet. Physiotherapy & postural exercise will also be helpful. If symptoms still persist, kindly consult a Neurologist & get a complete Neurological examination done. Certain investigations like complete blood count, serum electrolyte estimation, fresh estimation of blood pressure & blood sugar levels & nerve conduction studies will be helpful to rule out any pathological cause for the symptoms.X-ray & MRI of Cervico-dorsal spine can also be carried out to detect any nerve entrapment. Wishing you a Good Health. Take care.