Pea size lump on right side of neck, painless, for 5 months; can be moved side to side if pressed. Tingling/numbness in right arm; CRP & ESR raised (?)

Likely arthritis nec. The lump that can be moved under the skin is probably an incidental finding at location where pressure could cause symptoms of nerve root irritation even if there was no lump. High sed rate and CPR indicate inflammatory activity.