Everyone hates to have blood in the sputum. I sure do. Usually for me it is temporary after being sick. But if you have this chronically, I'd see your doctor. Here's a general article on blood in mucus. https://www.medicalnewstoday.com/articles/321563#causes-and-symptoms There are a lot of causes. Have you been sick lately? Do you have a chronic sinus issue like so many do? Maybe you have paranasal sinus disease? https://pubmed.ncbi.nlm.nih.gov/17888198/ Here is information on that. https://www.healthline.com/health/pansinusitis#treatment Do you do a netty pot? It can really help.