What Causes Coughing Up Of Pinkish Foamy Blood While On Medication For Bronchitis?

Hi there, I was diagnosed with bronchitis a week ago and 5 days ago I was given 3 tablets of Azithromycin antibiotics 500mg. 2 days ago, after finishing my antibiotics, I started coughing pink foamy blood about 3 tissues worth and just now my nose has started to bleed. I am wheezing and coughing. Please advise...