Is there such a thing as a rhinoplasty "touch up"?

From your description, it sounds possible that you may be a candidate for some small revisions to your original rhinoplasty once you have fully healed.  Sometimes these revisions can even be done in the office under local anesthesia.  It is best if you wait a full year to do these revisions as the body will continue to heal over the next few months.  I recommend you discuss your concerns with your surgeon to discuss your options.  Best of luck.

The
Rhinoplasty surgery is a very delicate procedure and does require a full year
of healing to fully see the final results. Patients are advised to wait the
full year as scar tissue can continue to expand creating swelling that may be
unnoticeable to anyone but you and your surgeon, especially in the tip of the
nose.
A secondary
rhinoplasty procedure may be required in about one in twenty cases as minor deformities
may appear only after surgery. This is quite unpredictable, even in patients of
the most skilled rhinoplasty surgeons.
It is
important to attend all your postoperative visits with your surgical team to
ensure that everything is healing accordingly.

Essentially what you are asking is if a revision is necessary. It is still too early to say. You should wait at least 1 year. However, it is possible to rasp the bone down and perhaps add a cartilage strut graft to give the tip more support.