Is it normal my nose looks so big after rhinoplasty? (Photos)

I am sorry to hear about your concerns. It is important to remember that at 12 days postoperatively, you are still very early in your healing process. Your nose will continue to heal and change over the next several months. Swelling can persist for several months up to a year after a rhinoplasty procedure. I recommend giving yourself some more time to heal and reevaluate this closer to the 6-month postoperative mark. Of course, it is important that you follow up with your surgeon regarding any concerns as he or she is best equipped to advise you in regards to your particular case. Best of luck!

The short answer to your question is yes, it is normal to have a "bigger nose" immediately after rhinoplasty is performed.  It takes a variable amount of time for the swelling to go down and how long it takes is influenced by skin thickness (with thicker skin taking longer), temperature, salt intake, among others.  
In terms of how long it takes for the swelling to go down, it can be highly variable but most of the noticeable swelling goes down in the first 6-12 weeks, with some swelling that can persist for a year or longer.  Every patient is different, best thing you can do is minimize salt intake and make sure you followup with your surgeon!  Best of luck through your recovery!

As you will experience, 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

At 12 days post operatively from rhinoplasty, significant swelling is still to be expected. It is not uncommon for swelling to be present for several months after surgery, depending on the type of surgery that was performed, skin thickness, implant, etc.  Gradual changes in the appearance of the nose may continue for up to one year. Be patient. 

12 days post op is completely normal to have swelling of this severity after rhinoplasty. It will take time for this to go down, especially with thicker skin. 
The only causes for concern would be increased bleeding, redness or extreme pain to the tip. These would be either signs of infection or septal hematoma and would be a good reason to see your surgeon asap. Otherwise, all looks as can be expected!