I'm having horrible pain and numbness and tingling sensation and tenderness and occasional swelling only in my hands. What is it? In june of last year I had tendonitis in my pinky finger. Shortly after I started to experience stabbing pain, extreme sensitivi

Possible arthritis. You may have developed arthritis in wrist which in turn causes swelling and pressure on the median and or ulnar nerve causing numbness and tingling.
It . It is hard to fully understand your description of symptoms such as these without further information regarding the diagnosis given thus far but there are several nerve related problems that can turn on or turn up the signal in nerves giving pain and discomfort. A peripheral neurpathy can be due to a variety of things, rsd can be ralted to an injured nerve or nerves, hormonal and metabolic problems including thyroid diseease and diabetes can affect circulation, nerve tissue and dryness of skin. Circulation conditions and temperture realted disorders can occur. Smoking can bring on a certain level of problems as well as certain medications it is equally inport to rule out anything focal such as a peripheral nerve compression like carpal tunnel or cubital tunnel or a simple tendonitsi that aslo may be acting as an underlying trigger for your problem. Talk to your physician about seeing a specialist or two with the idea that they may not solve your issue directly but can rule out some otherwise simpler diagnoses.