First of all, keep in mind that I am unable to diagnose you because I am unable to examine you, this forum is for educational purposes. From the history and symptoms you described it does sound like carpal tunnel syndrome. However, you are at risk for other possible explanations and I would suggest a complete workup.
The median nerve passess through a narrow cleft in the wrist and with inflammation from repetitive stress injury, etc. this nerve can be compressed and cause numbness in the hands (Generally index, middle and half of ring finger, along with weakness and atrophy in some cases). This numbness generally gets worse when you worsen the compression by bending the wrists or tapping on the wrist. I would recommend an EMG to look for slowing across the median nerve as it crosses the wrist. Some cases require tendon release surgery, while others are helped by wrist splints (it depends on the severity as determined by EMG).
You also decribed some arm numbness and possible past injury to your neck. This may represent cervical disc disease that can sometimes mimic carpal tunnel. For this I would recommend an MRI of your cervical spine.
The leg cramps are likely unrelated, but if you have the urge to move your legs due to a uncomfortable feeling, you may have restless leg syndrome (which can sometimes be the result of iron deficiency). If you are having muscle cramps in your legs, these can be caused by electrolyte imbalance, but usually does not have any identifiable cause. You should have your electrolytes checked. Quinine sulfate is often used for such tiypes of cramps. I hope this has been helpful.
Just for clarification, the finger numbness and leg cramping began at the same time two weeks ago.
For the cramps quinine sulfate works well. You can try the magnesium. You need to be on prednisone for a few days. The drug is toxic and evil and causes cancer, but it eliminates inflamation in zero time, and you need to put the fire out around those nerve sheaths. After a few days on prednisone (which won't kill you) go to Motrin for a week or two. Once the inflammation goes down, rest can help. Of course you need a physician for the prednisone.