The flesh at the back of my nostrils swell up so much at night that I can t Breathe through my nose. I m also very stuffy. One morning I woke up with such a terrible pain in my nose, and it was very congested so I blow out my nose (quite painfully​) and there was thick yellow mucous with blood and a bad odor I could smell inside my nostrils. Yesterday I coughed up black and yellow mucous (I m guessing it s because of the atmosphere that I was working in). So what could be wrong with me? I don t smoke, I exercise and try to a healthy balanced diet.