I have a weird cough (kinda gross)?

ive had this cough for a while. its not an itchy throat, its not much or a sore throat either. i dont really feel the coughing urge much but when i do cough i feel flem in my chest. i dont know where it is really, but it feels like its in my diaphram. somethimes i feel it come up too and its pretty nasty. ive had it for maybe 3 days now. im just wondering what it may be, how to get rid of it and what it may lead up to. im worried ill get bronchitis (sp?) or something from it. anyway, any kind of imformation or links will be greatly appreciated. thanks everybody! =)