Hit nose while sleeping 7 days post-op rhinoplasty. Started to bleed. Is it damaged? Will this impact results?

Even the most fastidious plastic surgery patients can't control what happens when they're asleep, so please don't feel bad. Events like yours are not uncommon. The fact that you only bled for a very short amount of time is promising, but it's difficult to say without examining your nose. You'll need to see your plastic surgeon to determine whether there was any significant damage.

It is difficult to say whether there is permanent damage at this point.  However, if it bled and is swollen after you hit it, you did hit hard enough that you may have shifted something inside.  It is hard to tell as there would've been swelling even prior to that.  I recommend that you contact your surgeon and let him/her know your concerns.