What Causes Painful Legs And Back Cramps, Finger Joints Locking, Discomfort, Pain?

For the past week or so I have been getting extremely painful cramps. Sometimes it is is my legs to the point where I am literally in the most pain I have ever been. Sometimes it is in my back so I am pretty much forced to kneel over like an old man. Sometimes the joints in my fingers completely lock up and I am unable to move them. This is causing extreme discomfort and pain to my day to day life and it is only getting worse. I figured I would ask here before going to see a doctor.