What does it mean when i cough blood?

im 18 and dont smoke, but i had a cold and fever with some coughing, i puked this morning and have been take 1 pill after a meal, the pill is for a cold and fever, and after my workout i was coughing quiet bad and i was a little bit of blood, and i ignored it, and after diner i coughed more blood... what does this mean... what do i do