Headache, pain from lower back till leg.

Respected doctor, I feel headache every morning. I feel something wrong with my head nerves. I cannot sleep in any head position and any type of pillow. Also, I feel severe and continuing pain from my lower back till my left leg including calves. Pain in all in the viens, I recon. Also I undergone left inguinal Hernia surgery 3 years back. I have started feeling the pain which forms part of above mentioned back pain till legs. It has all started after the surgery. I sometime think that there could be some viens which has been damaged or stuck which is causing severe pain in my lower left body. Please guide me whom to contact. Which specialization will this fall under. Is headache related to some neurological problem. Or shall I contact Orthopedic or shall I contact the Surgeon whom performed the surgery.