What is wrong with me?

well i have yellow snot coming out of my nose very stuffy am i more sick then i actually know? well i all started out on Sunday. i had a fever very congested and had a head ache because i had fluids in my head. then the next day i had a sore throat but not that bad. the next 2 days where find expect the fact i had alot of mucus. but today i found out when blowing my nose yellow snot came ut me mouth and nose it looked like a sold yellow. then i had 2 blow my nose again but yellow didn't come out my mouth but from the nose. the yellow faded and it keeps happening! WHATS WRONG WITH ME ?