In Theory Lifting moderate amount of weights could actually HELP with your growth. When you sleep your HGH levels raise "human growth hormone" and people who exercise with weights have higher levels of release of this hormone. although no study has ever been done on the subject in theory it is very possible that moderate weight lifting can help stimulate bone growth from many points not just limited to the heavier release of HGH.
In conclusion, Weight lifting does not stunt your growth and in fact might help it. The only possible way it could would be if you lifted a weight so heavy you did damage to bone and so on. However you will not soon be strong enough to lift a weight heavy enough to do such damage.
Simply make sure you use proper form throughout all your movements.