Full Body Pain. Which specialist to see?

My Mother is Facing Full body Pain from About Last 2 Months. She was Diagnosed by many doctors and Had gone through many Tests (Blood , Urine , Bone,Backbone) . But None Of them were able to Identify her condition . Homeopathy and Ayurveda were also tried But Nothing good happened but Her Condition is becoming worse day by day. She's having Pain in All over the body, Specially - Waist , Back , Legs. She feels intense Pain When someone Touches/Press at Some Parts of body. She is not able to walk or even Stand For Long... Doctors are only doing that they Only Give Bulk medicines Without even knowing the disease,in which most of them are 'Pain Killers' Her face has swollen.. And One more thing... that she always had this pain and she always used to Have Pain killers to get temporary relief.but this time no pain killers working... Can Anyone Understand Her Condition? Which Specialist to See? Sorry For my bad English.. Any type of help would be Appreciated...