Al Karama is for the Saleheen, while the miricle is for the Anbyaa. the difference is that one is sent by Allah as a challenge to the people, while the other is just a sign to help people stay on their Iman.
Not having a karama does not me you are less pious.. the companions of the prophet peace be upon him had less than the tabeen, but they were much better than them and had greater iman..
and not everything that is out of the ordinary is a karama, the dajal will come at the end of time with many strange things, but he is a liar.. Al Sahfe3y once said if you see a man walk on water and fly in the sky do not follow him until you are certain that he follows the quran and the sunna with the understanding of the companions