First off I wouldn't assume the worst! Secondly I would go see my GP...
Pins and needles can be caused by all sorts such as poor circulation, muscle tension, stress, anxiety, etc...
I had pains in arms and legs combined with pins and needles in my hands and feet... naturally I was pretty worried... went to the GP had various tests and in the end they diagnosed shoulder tension which was restricting blood flow... some prodding, poking and pain later and problem solved.