See a doctor. Things like this can pop up out of nowhere and just as quickly disappear. It could also be a problem that needs to be treated. A good doctor will be able to determine which scenario you're experiencing. I recommend starting with your GP, at least if s/he is someone you trust. If s/he feels unqualified to handle the situation, or it seems like he or she has some uncertainty, just ask for a recommendation for a good nearby neurologist.
The real important part right now is to not panic. While there could be a serious problem it is very unlikely and, from what you've shared, there's no reason to think that it is.
DX: NDPH, Recovered CRPS
RX: Lamictal, Provigil, Clonazepam, Ambien CR, Emsam, Namenda, Oxycontin, Oxycodone
PRN: Haloperidol, Zyprexa, Lodine, Zofran, Skelaxin