The "tension" that you feel in your neck is from inflammation, which is the body's natural response to injury.
Nerve roots exit between each vertebrae of your spine, on either side, in a space called the neural foramina. The word stenosis indicates a narrowing. Foramenal stenosis is caused when spine disease, in your case when a bulging disc blocks this space. Often with foramenal stenosis, disc or bone impinges on the nerve root, causing pain and injury to the nerve.
Encroachment on the spinal cord is an area of bone or soft tissue that pushes against the thecal space, where the spinal cord resides. Too much encroachment causes narrowing of the cord, leading to a condition called spinal stenosis.
Both of these conditions cause pain and get worse over time.
You should start with a good spine doctor. The weakness in your left arm may be a sign of nerve damage and this needs to be addressed immediately. Both the spine doctor and the ENT need to work together to develop a treatment plan for your multiple problems.
Have you tried some natural treatments like massage and acupuncture? These treatments are proven to ease the pain in a natural way, providing a very intense pressure inside the muscles.