ENT Question - I Was Diagnosed With A Sinus Infection

ENT Question - I was diagnosed with a sinus infection earlier in the week after traveling on several flights, ear plugged and couldn't pop. I'm at the end of Z-pak and generally feeling better. I was also given a nasal spray but haven't used in three or four days. This morning, after I showered, I blew my nose pretty hard and the mucous was bloody. It seemed generally consistent with mucous but the color was concerning - more red than I would expect. No situation is ever normal but is it normal to have this happen at the end of the cycle. Again, probably had the infection for two weeks and treated with Zpak for a week?

Thanks -