sounds like you have a sinus or chest cold. if the blood is just thin streaks then i don’t think theres much to worry about. nothing that a round of antibiotics wouldn’t cure. and if you smoke stop. if if more than streaky blood in your sputum [mucus flem] seek medical attention immediately. these could be signs of a more serious condition.
i've been coughing constantly for a few days now and just started coughing up a little bit of blood. at first i thought it was i cold i caught from my boyfriend. i've been coughing up phlegm with the consistency of slime in one of those science kits they have for kids. up until just now it's been yellow-green-ish but i've been coughing up less and less if anything and it's starting to hurt more and more. a few minutes ago i coughed up tiny bit of white phlegm with a little of red in it then again a few seconds later. right now my coughs are non-productive and hurt my lungs and throat.