Piggy nose after rhinoplasty. I had rhinoplasty 3 weeks ago. (Photos)

You have to give yourself some more healing time.  Your nose and surrounding areas are going to be swollen for a while and you should be consulting the surgeon that performed the procedure but give yourself some time before going back in so some of it can subside. It can take up to a year for final results.
Sincerely,
Philip J. Miller, MD, FACS Double Board Certified Facial Plastic Surgeon

You need to have patience with your body as it begins to heal. The skin, bone and cartilage are all traumatized during surgery. Inflammation (swelling) is the normal response and will help your nose to heal and look beautiful in the end. If, one year from now, you are unhappy with your nose, then that is the time to think about a revision procedure. Right now, concentrate on other things you like to do and let your nose and under eyes take the time to heal. I hope this helps.

As you have experienced, changes occur over the course of rhinoplasty healing. At first, the nose looks too "fat" and too "up," especially at the tip. Most of the dropping happens early, but there can still be significant changes over the full year and beyond.