What's Wrong with me? Doctor's again?10 points best answer?

What's Wrong with me? Doctor's again?Okay, so last Friday I started having this cough (sounded kinda like Croop my mom said, but it wasn't.) So It was not bad Friday, horrible Saturday, not too horrific Sunday, so I go to school on Monday...It is REALLY bad, and so I stayed on home Tuesday, Wednesday, and Thursday, but went to school today. On Thursday I wasn't coughing like at all (only a little at night) but then Friday it was horrible. I had a tennis match, when I was on the court and my mom was in the car (with door shut and window's up) she could hear me coughing! Saturday and Sunday it was really bad, and I went Trick-or-Treating...probably a bad idea. Today it is pretty bad too. So any idea? I don't think it is allergies, considering I don't have allergies. My teacher even asked me if I had bronchitis. Help? Oh I went to the doctors, but she didn't really find anything wrong, but I am starting to doubt...Thanks in advance! :DOh and I am kinda congested, headaches, mucusy cough, tired in general, runny nose (like especially when I sneeze)