Did you have any type of therapy or PT for the ruptured disk??
If nothing else perhaps for pain relief at least?
Have you read more about CRPS - do the symptoms fit for you?
we have a forum for it here -
With the whiplash injury I would also suggest reading on our Thoracic Outlet Syndrome forum- the nerve /or blood flow can become compressed/irritated in the area of the neck/collarbone , many nerves and blood supply to the arms run thru that area. Since you mention swelling , I wonder if it it a vascular issue, TOS can have nerve and/or vascular compressions/impingement.
Useful sticky thread with TOS info-
I wouldn't jump to a SCS until fully exploring both CRPS/RSD & TOS, also our Spinal forum for the ruptured disk & possible therapies.
Spinal Disorders & Back Pain -
And it could be a confusing mix of the disk, CRPS & TOS, but sometimes therapies can improve/relieve some of the pain.