I had septoplasty 3 weeks ago. when i look up one nostril i see white, which to me looks like bone and/or cartilage. is this normal?

No: I recommend that you followup with your surgeon.

Sounds concerning : Not knowing exactly what was done in your surgery, i would not say that is "normal" and suggest you call and/or see your doctor.

Rhinoplasty: It is very unlikely that you are seeing either. If you are concerned, you should contact your surgeon and be seen.

See your surgeon: It's hard to say what you are seeing. However, the important question after septoplasty really is "how are you breathing?" at 3 weeks you should be starting to notice an improvement in breathing compared to before surgery. Over the next few weeks, breathing continues to improve as internal swelling decreases. Check with your surgeon about what you see and how you feel.

Septoplasty: Have your surgeon evaluate this issue. it is possible you are seeing exposed cartilage.