question: I'm 54 years old, in fairly good health normally, don't smoke, never have. Yesterday morning woke up wtih a cough and flu symptoms.  Got worse through the day, developed pain and tightness in upper respiratory, dizziness and feeling that I'm not getting much O2 when breathing.  Cough this morning is very frequent, dry, what little I can cough out is thick and yellow.  trying to decide if I should wait this out or see the doc.  I had pneumonia once, many years ago, but it developed over several weeks.  This hit me very quickly over 24 hours.