I'm with Bram it sure sounds like classic RSD/CRPS but I sure hope not for your sake. Both Bram & Tessa have given good advice. I've had CRPS since Dec. 2012 after surgery for a badly broken wrist. My symptoms are from my finger tips to mid forearm but now to my elbow. I have very little range of motion in my hand and cannot straighten my fingers. I had never heard of it until then and I'm middle aged.
Since then I've done a ton of research and have been lucky to find a Pain Mgt. Dr. who is very knowledgeable about CRPS. This site is a great source of knowledge, advice and SUPPORT!
Again, I can pretty much echo their advice. Frequent GENTLE movement is good but not to cause pain. It's really good if you can find good Physical Therapy.
The only thing I can add is in addition to meds. is 1000 mg. vitamin C - that's supposed to prevent spread and I hurt more if i don't take it.
There's also American RSD Hope at RSDHope.org - they have lots of info. and I think there's a link to articles by Dr. Hooshmand, he's an expert on this subject.
Wishing you relief!