Numb & tingling back - get 3rd opinion or do nothing?

Went to Dr. after 2 days of numbness & tingling in back radiating up to my neck and jaw on the right side (no pain, just weird tingly/numb sensations.) I thought maybe a pinched or compressed nerve, but was diagnosed with shingles. Two weeks later symptoms persist and still had not a single pimple, blister, red mark or anything so I went for a 2nd opinion. Had thoracic spine x-rays & lab work done (typical blood work plus testing for inflammation) and today I'm told all came back negative - no problems. The numbness and tingling is getting more persistent and seems to be worse when I'm sitting or laying down. I do physical labor for a living and don't want to make it worse. Do I have the .01 percent of shingles cases that never develop any kind of rash? If so, how long will this weird sensation last? Would an x-ray miss something like a m or tumor pressing on a nerve? How long should I wait to see if this goes away?