How Can I Tell if my Nose is Just Badly Bruised?

It is often difficult for patients to examine and diagnose nasal injuries properly. In most cases, patients should see a physician for a formal exam and diagnosis. In some cases, imaging might be needed, but this is not something I routinely recommend for isolated nasal injuries. 
Ideally, the exam should be performed by a specialist in rhinoplasty such as a facial plastic surgeon. Be sure to see an expert.
Best,

Point tenderness and a new bump on the bridge are signs that you could have a nasal fracture. An X-ray or CT scan would be able to identify a fracture, although it is probably not necessary to get one. The decision on whether or not you nee treatment is made based on presence of new nasal obstruction or new nasal deformity. I would recommend you be seen by a surgeon who is familiar with nasal injuries and their treatment (facial plastics,ENT, or plastic surgeon).

  It is best have an examination by a ENT or  facial plastic surgeon to determine if there has been a fracture of the nose bones or septum, and to make sure that there is not a septal hematoma. Also important to make sure the upper lateral cartilages had not been fractured off the nasal bones. X-rays can also be helpful.

A direct examination would be helpful in determining if you have any septal deviation or other problems from the recent trauma. I would suggest an appointment with a specialist in septorhinoplasty for a proper diagnosis. Best regards, Michael V. Elam, M.D.