Everybody does not have the same reaction when they are criticized for some reason. There are some who take it negatively but that should not be the ideal case. For whatever or whichever reason you may be criticized take it in your stride. See it as a stepping stone so that you can get motivated and achieve the thing for which you have been criticized.
You may be criticized for something which is true or false. Do whatever it takes to prove the others that they are wrong. But to do so dont adopt any means which is harmful or dangerous. Sometimes it is best not to listen to what the others say. But only you can be the best judge of situations. Dont have any hard feelings against the critic. May be he has the best interests in his heart.
Criticisms can hurt you but instead of getting hurt seek the opportunity of personal growth. Dont think on the criticism too much. Learn your lesson properly and evaluate your progress so that you can improve on the point for which you were being criticized. A criticism is just like a reminder or a warning signal for something which is unwanted and not desirable. Learn to learn from your criticism then you can go a long way in your life.