Hello. Welcome to HCM.
Your cervical pain is radiating to shoulder and arm, which indicates that it can be radicular pain
. First you need to rule out cervical spondylosis
which is a common cause. You can get an MRI done for this. Uncommonly, there can be a disc prolapse
which will have sudden onset of pain. It will also be shown by MRI. Next, you must go in for regular exercise and physiotherapy
. Also, application of muscle relaxants would be beneficial.