Will It Be Obvious if a Patient Had a Rhinoplasty?

You should not need to share your personal medical history with anyone. A rhinoplasty should result in a natural, harmonious result that matches a person's face. Careful planning and communication between the doctor and patient is important in this regard.
Having said this, a natural result may still be dramatically different than how you look now. If this is the case for you, then your peers may or may not notice it on their own. The degree of change that you seek will determine this. Computer simulations may help you visualize what the changes you seek will look like.
Hope this helps.

When rhinoplasty has good aesthetic balance, others will think you look better for other reasons, a new haircut, losing weight, etc. It is only when rhinoplasty is overdone with a skin slope bridge, pinched tip, and pig like upturned nose that people will be clued in.