Dear lilyjames,
i think I was replying to you already somwhere else in this board but I believe it still would be good to say once again that
1. usually BFS develops exactly like it goes with you - it starts with innocent but annoying twitches, and then usually sensory disturbances become evident - like pins and needles, hot or cold spots, sudden pains, persostent or temporary soreness or stiffness, crampies, overall skin hyersensivitity, electrical shots, some people develop urticaria or rush etc. Then we usually start to complain for fatigue, perceived weakness (which is a feeling of being weak and out of resources), excersise intolerance etc. Then we realise that despite on unpleasant symptomes (some of prople here have constant nontop twithces for years, I think it is a very hard experience) we are not dying (at least not immedately) and come back to more or less active life.
2. tingling, internal buzzzing, twitches migrating from one body part to another are exactly what happens to typical BFS sufferer. The range is very weird and complete -from tiny soft buzzzing like there is a vibro under your sking to jerks and jolts moving the whole finger (I have read here that even the whole limb was moving!)
3. Pains in wrists and elbows are very common for those who are typing a lot. I personally do have that. Sometines my left forearm feels like connected to a battery - bzzzzz! bzzzzzz! from the wrist down to the elbow, quite boring. have you ever noticed if that pain is assosiated with any hand work? For me it is enough to take 3-4 kilo (6-8 lbs) from the grocery shop - and ooops... pains, shoots, stiffness all that stuff. Usually it became really bad on cold weather. really really bad, stiff etc.
Because I am quite sure now that at least part of BFS involves constant or temporary hyperexitability of neuro systems, all those pains and strange sensations become just evident for us (before we might not give any attention to it). As for my body, I believe it just complains in that way for far much overload than it can deal with ;( Anyway for many of us BFS had started after significant physical or mental stress or combination of it.
For tingling, cramps and stiffness I ususally use self-massage and warm clothes. As for extra skin sensiticity I do not know what exactly to share... but i know some people here use warm (not hot) bath and I know that the herb called Bidentis trpartita
http://en.wikipedia.org/wiki/Bidens_tripartita is widely used here in our country in order to smooth skin inflammation in children when they have their infant rush. Probably you have something similar in your country to add to the bath and get your skin less sore.
Anyway for BFS the picture you describe looks very very common.