Generally speaking, as long as the glasses are fitted properly, they won't cause pain on your nose. If they always give you a pain on the nose, it means that the glasses are too tight for you, which cause pressure on your nose. In this case, you should have your glasses adjusted. You can just adjust the nose pads on your glasses little by little untill they fit you properly, neither too tight nor too loose. If there are no nose pads on your glasses, you need to take your glasses back to the place you bought them and ask the worker to adjust the glasses for you. Or you can change for a new one that can fit you properly.