Nasal irrigation / nasal flushing and cleaning after a septorhinoplasty

How long should someone wait before doing a nasal rinse/ flush? I am 4 weeks post op and my inside nasal airways are clogged with massive amounts of dried blood and lots of crust. I use saline nasal spray on a daily basis 5x a day but does not seem to help or go through the nasal airway due to the blockage of the crusting. Would it be safe at this point to perform a nasal irrigation? I do not meet with my surgeon for another 2 weeks and would appreciate some feed back with your experience! thx