What could be the cause of my nose becoming short again after successful lengthening revision rhinoplasty?

I had a successful revision rhinoplasty four months ago. It was overshortened during my primary (upturned and quite short) then lengthened with septum . It looked good and i barely had swelling 10 days after the surgery. i had an accident on the 12th day.i hit my nose hard and it bled. my nose swelled up twice its size. it wasn't before that at all.4 months after the surgery it looks also much shorter- has the graft shifted from the hit or did it become softer and it has nothing to do with my accident ?