Let me explain you , what is Raynaud's phenomenon , so that you can understand the gravity of situation.
also occurs secondarily to other organic diseases such as atherosclerosis
, collagen diseases--specially scleoderma , Burger's disease, cervical rib
It also follows the use of industrial tools, e.g. chain ,saws,which bibrates at certain frequncies.
Thus in arm , atherosclerotic stenosis of the subclavian artery , scleroderma
, Burger's disease or the cervial rib & the scalene syndrome may be responsible.
Treatment is directed primarily to the casual lesions,though conservative treatment is also helpful.
As protection from cold , avoidance of pulp & nail-bed infections & the use odf vasodilator drugs are part of conservative regime that is advised in mild cases.
If not responding to these measures only operation is an option as SYMPATHECTOMY.
So in my opinion at once consult a surgeon or neurologist
and get his opinion.