My fingernails on my right hand grow at a faster rate than on my left hand. About every week or two, my right hand is at nail-trimming level (though I don't actually trim them every week or two, so they obviously grow more), whereas my left hand can go about a month or two before reaching that.
Am I right in guessing you are righthanded? I believe the reason for the different growing length is due to the hand itself. If you are right handed you will use it for more than the left so it uses more energy and could get hurt more often. For that reason your body sends more nutrients there causing it to advance at a quicker rate.
