If you have been hit in the nose, you may have fractured the nasal bones and septal cartilage
This can lead to narrowing of the nasal air passage, making airflow difficult. This may be causing you to mouth-breathe at night, which dries out and thickens mucus as it moves from the nose to the throat.
Try saline spray for relief. You may need to have nasal/septal fractue repair or septorhinoplasty.