First, direct icing is dangerous because it can lead to frostbite. Second after three weeks icing probably will not help. Always review instructions with your surgeon.
Using cold compresses for longer than 48 hours in not likely useful for preventing or resolving nasal swelling after rhinoplasty surgery. If you have concerns about your nasal appearance, you should make a follow-up visit with your surgeon for evaluation.
I hope this helps you.
Applying ice compresses on the nose after rhinoplasty surgery should not cause any distortion to the work that was done. If you were applying an abnormal amount of force on the nose or using ice that was too cold or too often, it is possible the nose could be affected.