I Am A 64 Yr. Old Male. About 7 Or

I am a 64 yr. old male. About 7 or 8 mnths ago I began having pain on the bottoms of my heels. I suspected plantar's faciilitis. I did the reqired stretches. No help at all. It evenutally moved into my feet and ankles. The pain began moving up the bones and muscles of my legs and into my knees then thighs and pelvic bones. I hurt hwen I walk. I have excrutiating pain when i rise from a seated position. The right inside top of my pelvic bones would hurt terribly when rising from a seated position. Th pain has started into my left top pelvic area. My left leg most nights during the early morn. hurts beyond description. Very often I have severe cramps along the area of my diaphragm. I stay short of breath. I hurt in the bones and muscle of my arms also. ( not as bad as my legs and hips when rising ) My hands and finger hurt and cramp often. I have seen many doctors. Nothing can be found. I am seeing a rheumatologist and cardiologist now.If nothing is found what am I to do?